Some screenshots would be nice :D. Thanks
Face Unlock is improved in the JB ROM. It has a "Liveness check" :) you must blink at the phone to unlock :D
Flash it with PIT 512 and repartition. For the password look in your inbox
You need to flash through Odin the JM2 eclair firmware wich will load a good bootloader. After this you can flash any ROM you like.
Good luck !! :)
For me it works if you keep the vol button pressed for 1-2 sec