That's very interesting. Even I (the author) didn't know that
If you have legally registered FlashFXP and it's not working right it could be caused by a previous crack, however this was not my intention. By deleting everything but your sites.dat and installing a fresh copy of FlashFXP your problems should go away. If they do not then the problem lies else where.
FlashFXP 1.4 is the latest and greatest. It's almost perfect, the bugs I am aware of are currently in the proccess of being wiped out. Hopefully within the next public release. The only major problem is the missing file/folder icons on some winXP systems.