Seems that if i'm correct GSM versions of the TP2 are mainly euro phones and ATT is TILT 2 version with 6.5 already installed? I also would check
http://forum.xda-developers.com/forumdisplay.php?f=491 for additional help
XDA developers is a great site forum .. I know they have some GSM versions..
http://forum.xda-developers.com/