[Gamersource]

That sounds like the memberinfo template. You are probably doing the search for

<div class="bigusername">$userinfo[musername] $userinfo[onlinestatus]</div>

and it is not finding it, right?

Anyway, it's because if you are upgrading, there is a most likely a </if> in there that isn't in the readme to seach for.

The best way to fix this is to simply look at your original template and do the edits in that one and then when you have all your edits done, use that in place of the old one.