What does "Colours" checkbox stand for ?
One more bug found. In FF when processing image is done we can still see message "Processing... 70%"
Did you observe the bug with the new code as well?
The checkbox stands for making the quantised palette of that particular image a "global palette". That palette can now be used to map the colors of other loaded images to it. Just choose "Global" in the "Colours" combobox to remap to that palette.