heres a link for dcd carrier cabs, uscc is in their , i checked .
http://dcd1182.n715dp.com/titan/carriers/
heres the link for gamedics tut. for unlocking and flashing custom roms there you will also learn how to create your own.
http://forum.ppcgeeks.com/showthread.php?t=33857
but if you want to flash pre made one click on the titan upgrades. but you still have to unlock it. good luck.
also note under gamedics tutorial he will show you how to flash anything via sd card