can't add or delete an object from a group; ungrouping loses actions
The "group" concept seems to be really brittle. While I can edit objects that are within a group, I can't add anything to a group or delete anything that's within a group without ungrouping. Unfortunately, ungrouping destroys any actions that I have programmed that affect that group, so I really don't want to do that.
A prototyper is all about creating things incrementally and tweaking things around as you go. It's really counter to the prototyping mindset to be stopped like this when I want to make a small change to a group that I've already created. Please make it possible to add/delete objects to/from a group.