Sorry for the delay but I found building redistributable python apps in Windows is a pain in the *** ;(
In the meantime, though, I went further, so now KCC build
ePub2.0-valid files, then you can choose to give them to
kindlegen or to stay with them alone (e.g. if you own a Kobo :P )
The GUI should make all the dirty work on your behalf, providing you have
kindlegen.exe in your PATH (e.g. you can copy it to c:\Windows\).
Feedback appreciated!