had no problems when i used my FF 800 in my old PC core 2 duo with XP SP 2 (but i used the firewire 400 plug)

Now i just bought the new iMac 27' core i7 with OSX 10.6.2 and i m trying to install my FF 800.
The Firewire 800 plug of my iMac works good (i tried a hard disc on).
I downloaded the latest drivers 2.65 for OS X SL.
The install process seems to be good following your recommandations:
FF 800 plug in into the Imac, Switch on the FF 800, Drivers Install, reboot.
I have 2 Icons: Settings and Mixer, but it's impossible to open them!
i tried every possible installations way, switch on or off after the boot machine
In my Fireface interface, the HOST light is red.

OK the problems is the link FW800 to FW 800 ( it's sure because the cable is good)

Fireface 800 is OK(FF settings open) on iMac when i use  FW400 to FW800 link .

but it's not normal , why the link FW800 to FW800 doesn't work?