Unfortunately the site you gave money to is a scam, I got caught out as have loads of people! Unless you have done it recently and can get your credit card company to cancel the transaction i'm afraid you have lost the money. sites like that suck!!
you shouldn't have to re-download limewire but to get the pro version you do have to pay, this is NOT a scam its just how they afford to develop the software just makes sure you do it from the link within limewire.
playing the avi files I am still struggling with, I know its possible to download players that will but all of the websites look too confusing, the other option is to download the codecs.
To do this search the forum for avi viewer and you should get up a message with some links thats what im trying to do
happy sharing !!