I've got a Gateway M7305u with some specs:

Intel T3200 Dual-Core
Intel GL40 Chipset
GMA 4500HD video card

I have Leopard running fine on a partition and followed the guide I found here

Install seemed to go fine, but booting into SL just sticks at apple loading screen. Booting into Single User Mode got me this error:

Error: Uncompressed file not length recorded
Error: couldn't uncompress plist file from multikext archive entry 0

I pulled a graphics kext from here.

I can provide more details on my install if desired, but I've been looking and looking in forums and wikis, and I'm just frustrated and lost at this point.
Has anyone encountered this issue before/know of the possible cause or resolution?