Josh,
You got it... I just added for clarification the correct string in PP 3.2.1 to replace.
Change this:
$profilelink = "{$Globals['vbulletin']}/showprofile.php?Cat=&User=$tusername&Number=$tuserid";
to:
$profilelink = "{$Globals['vbulletin']}/showprofile.php?Cat=&User=$tuserid";
This makes the Profile links work!
The only problem that I seem to still have is PP does not recognize a user as being logged in after they logged into UBB. They have to login seperately to PP and UBB?