If you have LW 4.12.3 then you won't be redirected to artist direct or elsewhere.

I have never heard of blank screen problems on mac osx other than those using Jaguar may have some similar issues. Which OSX version are you using? It sounds like 10.2. If that's the case, try changing skins. ie: Choose View>Change skin from LW's menu bar.

And take Foolofthehill's advice here to avoid fake files: http://www.gnutellaforums.com/showthread.php?t=58496