Workflow interactive chart not created/rendered correctly

[czhci]

In this entry, an extra "ImageJ" block is created at the bottom right. Couldn't be corrected by editing the entry content. These "extra" ones come from previously added workflow steps, but removed after edited/updated the workflow. They still stay and get rendered. (An extra example here)
And in this entry, when consecutive steps are pointing to the same component/tool, the the rendered arrow points at weird location.