Well youl'll be happy to know that I got Mac OS Snow working on my MSI X58 Platinum board! Sweeeet! =^)
You were probably telling yourself "Its gotta work", and it does! I installed it using your method, however, I modified it slightly. I utilized my AMD Athlon 64 w/ 10.5.6 (which was iPC, by the by, jeje) and I followed your steps of installing the OSInstall, Bootloader, DSDT (msi-mobo), kexts, to the Tee (I also added the HDAAudio). It was much faster than installing a distro and restarting et al. sort of like installing off of a HardDrive! Once everything was installed I plugged the SATA into ICH10SATA1 and it booted up! no Panics, no Boot Strings, just beautiful!
Everything worked except for Video, so I installed QE_CI_for_Exotic_cards_10.6.1.pkg (for my ATi 4890 OC) and I Enabled QuartzExtreme and GL w/ OSX86Tools and rebooted, voila, brand new Mac w/ Full QE/CI on an overclocked Radeon and - perhaps, soon to be overclocked motherboard. =^) I could not be happier!
I know you could call my method of installation a "cheat" and I realize that some people might not have the option of installing off of another Mac but this is what I guess I had to do to get my motherboard working with Snow Leopard. Thanks a bunch for the help x986123, now I am up and running! Awesomeness.