Hey
I actually tried to follow your method since the usb boot didn't work. I got an extra 40gb IDE harddisk from a friend.
I installed Kalyway 10.5.2 on the 40 GB harddisk (MBR) using my gigabyte motherboard as it doesn't work on G33BU.
While using the same gigabyte motherboard, I installed Snow Leopard on a 250 GB SATA harddisk sticking to your guide strictly.
Just before rebooting, I installed the 250 GB harddisk on my G33BU and tried booting from it.
Now I get stuck. The screen freezes on "Initialized MAC framework successfully".
And in the questions you asked, did I have to manually copy kexts for chameleon to the Extra/Extensions folder?
Is the problem because I had installed it on the gigabyte board and then transfered it to the intel board?