1/30/2013 1:21:03 AM
RE:Media Library Update file
What version of FireFox do you use?
Also, I would like to recommend the upgrade - there was a bug when updating files. so, even if it is bug, it will be fixed in v7 only (However, I am unable to reproduce it on v6 and v7 of Kentico). So the upgrade would be necessary anyway.
I am sorry for this inconvenience.