Many programmes are marked as OSX, but are in fact .exe which will not work on Mac..... misslabled for fome reason by idiots
The files you should look for are .dmg but sometimes you will not know what they are unless you have downloaded them.
Personally I steer well clear of Programmes on the network and only obtain them from 100% trusted sources, and Gnutella is most certainly not one. but I know good progs can be found, and at least we Mac users don't have to worry about viruses .... (yet), so a bad download will not destroy our computers