Okay wierd coding after the line "// call get_profiledata to get all the links possible" in showproduct.php
$upostline[$itemnum] = $postline; is stated twice, and $culoc is never used as far as I can see.
$clocation is used in the if statements (f ($clocation != "") $uclocation[$itemnum] =...) but I'm pretty sure that it should be $culoc, same error goes for the signature data.
I think that section that deals with profile data needs a bit of a rewrite/tidy up
As is, if you pass data in from ib2.php in $userprofile[5] it's not used or displayed using standard templates.
I haven't tested yet but I guess the same goes for the signature data.
Apologies, suggestion has progressed into a bit of a bug report