I tried using -x -f and got problems with AppleRTC, I was able to pass it by forcing it to run in 32bit mode; however, it still got stuck, without any kernel panic msgs. The last msgs on the screen are::
Resetting IOCatalogue.
HDAEnabler: Copyright (c) by Kabyl
HDAEnabler: 05/05 2008 Added SP-Audio support by Taruga
HDAEnabler: 03/07/2009 Compiled for 32/64-bit by Taruga