First, let me say that this thread is in the wrong place, this is where one posts to release mods.
Second, as a Mac user, I can say with finality that many, and most mods work on mac. I have my override folder right now that's stuffed with various different ones at the moment.
The only mods that macs tend to have problems with are ones that use their own installers, as macintoshes can't use .exe files, ones that install with the TLSpatcher are tougher to get working.
But to sum it up, mods do work fine on the mac.
Is your override folder in the right place? It should be right inside the main KotOR folder, in wherever you put the folder when you installed it.
Are you one of those poor Macintosh gamers that are in the possession of Empire at War, yet because of the scarcity of Mac players out there you have nobody to play against? If you are, PM me if you want to set up a game.