diff --git a/.gitignore b/.gitignore
index 3637755ae..67ebd71e8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -172,3 +172,7 @@ mock_display_output/
 # Static Files added by install/update_vendors.sh
 /src/static/scripts/
 /src/static/styles/
+._*
+.DS_Store
+src/config/device.json
+src/static/images/current_image.png
diff --git a/src/blueprints/apikeys.py b/src/blueprints/apikeys.py
index 3a87fc1fb..a2850c37d 100644
--- a/src/blueprints/apikeys.py
+++ b/src/blueprints/apikeys.py
@@ -34,6 +34,8 @@ def write_env_file(filepath, entries):
             f.write("# InkyPi API Keys and Secrets\n")
             f.write("# Managed via web interface\n\n")
             for key, value in entries:
+                # Strip newlines to prevent injection of extra entries
+                value = value.replace('\n', '').replace('\r', '')
                 # Quote values with spaces or special characters
                 if ' ' in value or '"' in value or "'" in value:
                     value = f'"{value}"'
diff --git a/src/blueprints/plugin.py b/src/blueprints/plugin.py
index b7a80d860..6f32e1d21 100644
--- a/src/blueprints/plugin.py
+++ b/src/blueprints/plugin.py
@@ -235,7 +235,9 @@ def update_now():
     try:
         plugin_settings = parse_form(request.form)
         plugin_settings.update(handle_request_files(request.files))
-        plugin_id = plugin_settings.pop("plugin_id")
+        plugin_id = plugin_settings.pop("plugin_id", None)
+        if not plugin_id:
+            return jsonify({"error": "plugin_id is required"}), 400
 
         # Check if refresh task is running
         if refresh_task.running:
@@ -249,7 +251,7 @@ def update_now():
 
             plugin = get_plugin_instance(plugin_config)
             image = plugin.generate_image(plugin_settings, device_config)
-            display_manager.display_image(image, image_settings=plugin_config.get("image_settings", []))
+            display_manager.display_image(image, image_settings=plugin_config.get("image_settings") or [])
 
     except Exception as e:
         logger.exception(f"Error in update_now: {str(e)}")
diff --git a/src/blueprints/settings.py b/src/blueprints/settings.py
index 6f3c013e4..a402378bf 100644
--- a/src/blueprints/settings.py
+++ b/src/blueprints/settings.py
@@ -1,7 +1,7 @@
 from flask import Blueprint, request, jsonify, current_app, render_template, Response
 from utils.time_utils import calculate_seconds
 from datetime import datetime, timedelta
-import os
+import subprocess
 import pytz
 import logging
 import io
@@ -86,10 +86,10 @@ def shutdown():
     data = request.get_json() or {}
     if data.get("reboot"):
         logger.info("Reboot requested")
-        os.system("sudo reboot")
+        subprocess.Popen(["sudo", "reboot"])
     else:
         logger.info("Shutdown requested")
-        os.system("sudo shutdown -h now")
+        subprocess.Popen(["sudo", "shutdown", "-h", "now"])
     return jsonify({"success": True})
 
 @settings_bp.route('/download-logs')
diff --git a/src/config.py b/src/config.py
index 4761f4592..623d5dd5b 100644
--- a/src/config.py
+++ b/src/config.py
@@ -20,6 +20,7 @@ class Config:
     plugin_image_dir = os.path.join(BASE_DIR, "static", "images", "plugins")
 
     def __init__(self):
+        load_dotenv(override=True)
         self.config = self.read_config()
         self.plugins_list = self.read_plugins_list()
         self.playlist_manager = self.load_playlist_manager()
@@ -60,10 +61,10 @@ def write_config(self):
         with open(self.config_file, 'w') as outfile:
             json.dump(self.config, outfile, indent=4)
 
-    def get_config(self, key=None, default={}):
+    def get_config(self, key=None, default=None):
         """Gets the value of a specific configuration key or returns the entire config if none provided."""
         if key is not None:
-            return self.config.get(key, default)
+            return self.config.get(key, default if default is not None else {})
         return self.config
 
     def get_plugins(self):
@@ -114,7 +115,6 @@ def update_value(self, key, value, write=False):
 
     def load_env_key(self, key):
         """Loads an environment variable using dotenv and returns its value."""
-        load_dotenv(override=True)
         return os.getenv(key)
 
     def load_playlist_manager(self):
diff --git a/src/display/abstract_display.py b/src/display/abstract_display.py
index e05108772..3a269c74b 100644
--- a/src/display/abstract_display.py
+++ b/src/display/abstract_display.py
@@ -30,7 +30,7 @@ def initialize_display(self):
         """
         raise NotImplementedError("Method 'initialize_display(...) must be provided in a subclass.")
 
-    def display_image(self, image, image_settings=[]):
+    def display_image(self, image, image_settings=None):
         """
         Abstract method to display an image on the screen.  Implementations of this
         method should handle the device specific operations.
diff --git a/src/display/display_manager.py b/src/display/display_manager.py
index 71d9459f3..a0eea91b8 100644
--- a/src/display/display_manager.py
+++ b/src/display/display_manager.py
@@ -54,7 +54,7 @@ def __init__(self, device_config):
         else:
             raise ValueError(f"Unsupported display type: {display_type}")
 
-    def display_image(self, image, image_settings=[]):
+    def display_image(self, image, image_settings=None):
         
         """
         Delegates image rendering to the appropriate display instance.
@@ -67,6 +67,9 @@ def display_image(self, image, image_settings=[]):
             ValueError: If no valid display instance is found.
         """
 
+        if image_settings is None:
+            image_settings = []
+
         if not hasattr(self, "display"):
             raise ValueError("No valid display instance initialized.")
         
diff --git a/src/display/inky_display.py b/src/display/inky_display.py
index a4c8bccb8..ec23f9faf 100644
--- a/src/display/inky_display.py
+++ b/src/display/inky_display.py
@@ -37,7 +37,7 @@ def initialize_display(self):
                 [int(self.inky_display.width), int(self.inky_display.height)], 
                 write=True)
 
-    def display_image(self, image, image_settings=[]):
+    def display_image(self, image, image_settings=None):
         
         """
         Displays the provided image on the Inky display.
diff --git a/src/display/mock_display.py b/src/display/mock_display.py
index de67fa2e4..5fe9a1419 100644
--- a/src/display/mock_display.py
+++ b/src/display/mock_display.py
@@ -20,7 +20,7 @@ def initialize_display(self):
         """Initialize mock display (no-op for development)."""
         logger.info(f"Mock display initialized: {self.width}x{self.height}")
         
-    def display_image(self, image, image_settings=[]):
+    def display_image(self, image, image_settings=None):
         timestamp = datetime.now().strftime("%Y%m%d_%H%M%S")
         filepath = os.path.join(self.output_dir, f"display_{timestamp}.png")
         image.save(filepath, "PNG")
diff --git a/src/display/waveshare_display.py b/src/display/waveshare_display.py
index 96dc01af6..5d428f59b 100644
--- a/src/display/waveshare_display.py
+++ b/src/display/waveshare_display.py
@@ -100,7 +100,7 @@ def initialize_display(self):
                 write=True)
 
 
-    def display_image(self, image, image_settings=[]):
+    def display_image(self, image, image_settings=None):
         
         """
         Displays an image on the Waveshare display.
diff --git a/src/inkypi.py b/src/inkypi.py
index 5dc4de57b..e5f37ad04 100755
--- a/src/inkypi.py
+++ b/src/inkypi.py
@@ -11,13 +11,8 @@
 import warnings
 warnings.filterwarnings("ignore", message=".*Busy Wait: Held high.*")
 
-import os
-import random
-import time
 import sys
-import json
 import logging
-import threading
 import argparse
 from utils.app_utils import generate_startup_image
 from flask import Flask, request, send_from_directory
@@ -98,7 +93,7 @@
 
     try:
         # Run the Flask app
-        app.secret_key = str(random.randint(100000,999999))
+        app.secret_key = os.urandom(24).hex()
 
         # Get local IP address for display (only in dev mode when running on non-Pi)
         if DEV_MODE:
@@ -109,7 +104,7 @@
                 local_ip = s.getsockname()[0]
                 s.close()
                 logger.info(f"Serving on http://{local_ip}:{PORT}")
-            except:
+            except OSError:
                 pass  # Ignore if we can't get the IP
 
         serve(app, host="0.0.0.0", port=PORT, threads=1)
diff --git a/src/model.py b/src/model.py
index df2f4b1cf..93debba81 100644
--- a/src/model.py
+++ b/src/model.py
@@ -67,9 +67,9 @@ class PlaylistManager:
     DEFAULT_PLAYLIST_START = "00:00"
     DEFAULT_PLAYLIST_END = "24:00"
 
-    def __init__(self, playlists=[], active_playlist=None):
+    def __init__(self, playlists=None, active_playlist=None):
         """Initialize PlaylistManager with a list of playlists."""
-        self.playlists = playlists
+        self.playlists = playlists if playlists is not None else []
         self.active_playlist = active_playlist
 
     def get_playlist_names(self):
@@ -306,14 +306,6 @@ def should_refresh(self, current_time):
                 return True
 
         # Check for scheduled refresh (HH:MM format)
-        if "scheduled" in self.refresh:
-            scheduled_time_str = self.refresh.get("scheduled")
-            latest_refresh_str = latest_refresh_dt.strftime("%H:%M")
-
-            # If the latest refresh is before the scheduled time today
-            if latest_refresh_str < scheduled_time_str:
-                return True
-        
         if "scheduled" in self.refresh:
             scheduled_time_str = self.refresh.get("scheduled")
             scheduled_time = datetime.strptime(scheduled_time_str, "%H:%M").time()
diff --git a/src/plugins/base_plugin/base_plugin.py b/src/plugins/base_plugin/base_plugin.py
index 6a0ec2aad..0934087a3 100644
--- a/src/plugins/base_plugin/base_plugin.py
+++ b/src/plugins/base_plugin/base_plugin.py
@@ -84,7 +84,9 @@ def generate_settings_template(self):
         template_params['frame_styles'] = FRAME_STYLES
         return template_params
 
-    def render_image(self, dimensions, html_file, css_file=None, template_params={}):
+    def render_image(self, dimensions, html_file, css_file=None, template_params=None):
+        if template_params is None:
+            template_params = {}
         # load the base plugin and current plugin css files
         css_files = [os.path.join(BASE_PLUGIN_RENDER_DIR, "plugin.css")]
         if css_file:
diff --git a/src/plugins/calendar/calendar.py b/src/plugins/calendar/calendar.py
index 67d5b008c..c009c85ac 100644
--- a/src/plugins/calendar/calendar.py
+++ b/src/plugins/calendar/calendar.py
@@ -74,7 +74,11 @@ def fetch_ics_events(self, calendar_urls, colors, tz, start_range, end_range):
         parsed_events = []
 
         for calendar_url, color in zip(calendar_urls, colors):
-            cal = self.fetch_calendar(calendar_url)
+            try:
+                cal = self.fetch_calendar(calendar_url)
+            except RuntimeError as e:
+                logger.warning(f"Skipping calendar due to fetch error: {e}")
+                continue
             events = recurring_ical_events.of(cal).between(start_range, end_range)
             contrast_color = self.get_contrast_color(color)
 
diff --git a/src/plugins/weather/weather.py b/src/plugins/weather/weather.py
index e5d829e83..6804b2f52 100644
--- a/src/plugins/weather/weather.py
+++ b/src/plugins/weather/weather.py
@@ -340,16 +340,17 @@ def parse_open_meteo_forecast(self, daily_data, units, tz, is_day, lat):
 
         forecast = []
 
-        for i in range(0, len(times)): 
-            dt = datetime.fromisoformat(times[i]).replace(tzinfo=timezone.utc).astimezone(tz)
-            day_label = dt.strftime("%a")
+        for i in range(0, len(times)):
+            forecast_date = date.fromisoformat(times[i])
+            day_label = forecast_date.strftime("%a")
 
             code = weather_codes[i] if i < len(weather_codes) else 0
             weather_icon = self.map_weather_code_to_icon(code, is_day=1)
             weather_icon_path = self.get_plugin_dir(f"icons/{weather_icon}.png")
 
-            timestamp = int(dt.replace(hour=12, minute=0, second=0).timestamp())
-            target_date: date = dt.date() + timedelta(days=1)
+            dt = datetime(forecast_date.year, forecast_date.month, forecast_date.day, 12, 0, 0, tzinfo=tz)
+            timestamp = int(dt.timestamp())
+            target_date: date = forecast_date
 
             try:
                 phase_age = moon.phase(target_date)
diff --git a/src/refresh_task.py b/src/refresh_task.py
index f554e2adb..ab689dd2b 100644
--- a/src/refresh_task.py
+++ b/src/refresh_task.py
@@ -143,7 +143,8 @@ def manual_update(self, refresh_action):
 
                 self.condition.notify_all()  # Wake the thread to process manual update
 
-            self.refresh_event.wait()
+            if not self.refresh_event.wait(timeout=300):
+                raise TimeoutError("Manual update timed out after 300 seconds")
             if self.refresh_result.get("exception"):
                 raise self.refresh_result.get("exception")
         else:
diff --git a/src/utils/app_utils.py b/src/utils/app_utils.py
index 24a7ce6cd..36fd7e8c1 100644
--- a/src/utils/app_utils.py
+++ b/src/utils/app_utils.py
@@ -142,7 +142,9 @@ def parse_form(request_form):
             request_dict[key] = request_form.getlist(key)
     return request_dict
 
-def handle_request_files(request_files, form_data={}):
+def handle_request_files(request_files, form_data=None):
+    if form_data is None:
+        form_data = {}
     allowed_file_extensions = {'pdf', 'png', 'avif', 'jpg', 'jpeg', 'gif', 'webp', 'heif', 'heic'}
     file_location_map = {}
     # handle existing file locations being provided as part of the form data
diff --git a/src/utils/image_utils.py b/src/utils/image_utils.py
index 383ba1646..9870f2b46 100644
--- a/src/utils/image_utils.py
+++ b/src/utils/image_utils.py
@@ -20,21 +20,26 @@ def get_image(image_url):
     return img
 
 def change_orientation(image, orientation, inverted=False):
-    if orientation == 'horizontal':
-        angle = 0
-    elif orientation == 'vertical':
+    if orientation == 'vertical':
         angle = 90
+    else:
+        angle = 0
 
     if inverted:
         angle = (angle + 180) % 360
 
     return image.rotate(angle, expand=1)
 
-def resize_image(image, desired_size, image_settings=[]):
+def resize_image(image, desired_size, image_settings=None):
+    if image_settings is None:
+        image_settings = []
     img_width, img_height = image.size
     desired_width, desired_height = desired_size
     desired_width, desired_height = int(desired_width), int(desired_height)
 
+    if img_height == 0 or desired_height == 0:
+        raise ValueError("Image dimensions must be non-zero")
+
     img_ratio = img_width / img_height
     desired_ratio = desired_width / desired_height
 
@@ -61,7 +66,9 @@ def resize_image(image, desired_size, image_settings=[]):
     # Step 3: Resize to the exact desired dimensions (if necessary)
     return image.resize((desired_width, desired_height), Image.LANCZOS)
 
-def apply_image_enhancement(img, image_settings={}):
+def apply_image_enhancement(img, image_settings=None):
+    if image_settings is None:
+        image_settings = {}
     # Convert image to RGB mode if necessary for enhancement operations
     # ImageEnhance requires RGB mode for operations like blend
     if img.mode not in ('RGB', 'L'):