3. If anyone could point me at a good sample plugin that can show me how
to do UI stuff (I need a file browser or at least a text box and a
couple checkboxes and buttons in the configure dialog, and hopefully a
pop-up progress bar or two) I'd really appreciate it. This entire
section in the guide simply says "TODO."
I don't think there's anything that does quite all of that, but all of the included Python plugins--Artwork, Lyrics, Magnatune, and Jamendo--do UI things in RB, so maybe you could glean some things from them. Also, the PyGTK docs and tutorial are very accessible.
Cheers,
Andrew