http://jpcsplmforum.comyr.com/index.php
The copyright is still there, so no. You're allowed to modify it however you want. Just look at mine.
There isn't a link back to him.
There was when I checked it. He edited it to be similar to mine. Unfortunately
a) I asked for permission before altering the copyright.
b) Mine is still a link.
http://ratbustersanonymous.com/forum/
I altered his theme too...almost completely and I still left the copyright for him. Justin deserves it for his great set of themes he created for mybb.
As long as you leave copyright you can alter it however you want.
O, he alter it altogether