This is quite unusual. Make sure you're not installing on top of OSX i.e. make sure the partition is reformatted. You say it freezes 20 seconds into the boot?

Maybe redump iatkos to the partition with ddmac to make sure the source hasn't been altered or anything.

Did you change something in the BIOS?

I have to admit installation didn't yield always the same exact result i.e. as I've explained in my other posts, the trackpad thing, working oob sometimes and some other times needing more configuration but I installed many many times Iatkos v7 with different kexts and it would boot to the GUI almost everytime.

I don't know how to help...

Hope you find why it does that!