While playing if I right click fast it pretends that I didn't click at all, so nothing happens. Its fine if I click once every 2 seconds, but that's not really acceptable. Has anyone heard of such a problem? Anyone has any suggestions for a fix?

I tried playing with my original cd, 2 different torrented versions, with and without voobly patch, in all compatibility modes, its the same in all of them.

Moved to Technical Support Forum.

Hi welcome to tech support.
Does the same problem happen offline in singleplayer mode?
This sounds like mouse lag, have a look at the following thread and try the solution:
http://www.voobly.com/forum/thread/253679