Hello,
I just tested it, using the fill tool, and saved, and the color did
change. Keep in mind you must save through the menu or if auto-save is
on 5 minutes + must elapse or the changes you make will not keep. So
try making the shape, then using the fill bucket change its color, and
then save.
If the color still is not changing properly please provide me with the
steps to replicate this bug so that I can figure out the issue and fix
it.
Jonathan