I had GEHOT CFW with a couple of .pkg's (FTP, Games,..)
Then, I pressed the ON-button and hold it until the ps3 go back out again. Then when he is out, i press again the ON-button until the Ps3 Beebs twice.
When your in the recovery menu, go to system update. Then just follow the on screen things. Before you do this all, be sure that you maked a map in your USB called : PS3. In the map PS3 you make a MAP called UPDATE. In the map update you put your CFW in.
And with a little luck you have the CFW installed on your ps3.