Dont know if this is a real bug or a 'feature'.
When dragging a selection of directories to another panel copying starts and copy window is shown. This copy window is however not sticky and doesnt stay on top of the FC window.
So when you click on the FC window the copy window drops all the way to the desktop.
Especially of you're copying large files that take a while, this can lead to some trouble.
Since from the FC window there is no sign if the copying is done or not, the copy window is hard to find and FC doesnt appear to lock the files you are copying.
When I inadvertantly deleted a file in a dir that still was part of a copy activity. After a minut FC reached the point where the file was now gone and gave an error msg (sorry dont know exactly which). After that FC started acting weird. Couldnt drag nor copy files anymore. Not even when I restarted.

After some cursing and research, it appeared that my .ini file was changed by this all and was now much smaller than before???

I restored the .ini file from a backup and then FC worked OK again.

Suggestions:

- Lock files that are copied/moved
- Make copy window stick on top of the FC window so it's always clear what the status is