Thanks, Lilybiri-- I now remember reading that table when Captivate 6 first came out, but it's been a while and I'd forgotten about it. 
It's good to know that at least some of this (variables not converting properly) is probably fixed in a patched version. I didn't really expect the Advanced Actions to convert, but I found it odd that when I did try deleting them before converting the project, it didn't actually help me in this case. Oh well~ I may investigate further, but for the moment I'm going to stay away from converting projects until I have a patched, non-trial version.
Luckily I can replace the widgets with smart shape buttons (hurrah! I've been coveting them since you first started writing about them).