I was trying Leo4all v2, but now I'll try to follow your howto.
My PC is very much yours, Jimmy (the details are on my sig, but the main difference is that I use IDE devices instead of SATA).
Since P5K-SE has only one IDE port, I've had to put both my HD and DVD drive on the same flat cable, and I think this is giving me all troubles I've got.
I've found some tips, but nothing worked. I've tried cpus=2 (for the Core 2 Duo) and cpus=1 (since I've readed that this was needed in some threads), and rd=disk0s2 seemed to give some result for the IDE problem, but the boot only stopped in other fase.
I wanna know wich flags you had to give on DVD startup.