Thanks for sticking with it. I have added a new version to the download options to try to get it working for you if you still wish to try it out or help me debug. Download PDC2-v2.01-diagnostic.html
It includes:
- less brittle empty-canvas targeting for double-click node creation
- desktop double-click no longer disabled just because the browser reports touch capability
- Shift+D toggles node-creation debug logging (copy this and send it back here if it's still giving you trouble)
Thanks for your patience!