Comment 7 for bug 520186

this was mentioned to me in a conversation about this bug.
(After testing, this seems to be a problem with gtk+-2.0 pixmap engine. Any theme using the pixmap engine crashes with fspot in the same manner.)

a workaround for now was changing themes, that let me get f-stop working.
check out comment 10 from the forums

http://ubuntuforums.org/showthread.php?p=8841324