Disclaimer: Afaik I can only make 1 post per day as newbie on discourse, so I put both topics in one thread.
(1) Dia v0.97 does not allow to paste bitmaps. Adding that feature would be really helpful so explain certain GUI classes within class diagrams.
(2) If you don’t use UML regularly you get confused with where arrows have to point, so an explanation right on top of the icons would be nice.
I suggest something like this in the left side pane:
While the on-hover-hints are something like:
- B realizes / implements interface A
- B inherits class A