petri: for your problems with kazaa, i would recommend using only one p2p client. some clients have a thing with competition, and disable all other p2p clients besides their own! heh, stupid i know but what can we do
but ya know..
just incase that dosen't work, then i would try doing what you said, un-installing kazaa and then re-installing and re-registering also (if that is what you said, i just browsed through the post) hehe..