The only bit of code that I see that looks suspect, bur should work, is on line 597:
if (function_exists("rel2abs")) $GoToPage = $GoToPage?rel2abs($GoToPage,dirname(__FILE__)):"";
It is an if conditon without braces around the action " if (conditon) {action;} This is supposed to be kosher, but I would maybe add the braces and see what happens:
if (function_exists("rel2abs")) { $GoToPage = $GoToPage?rel2abs($GoToPage,dirname(__FILE__)):"";}
Grasping at straws though. ;)