Sorry, you get the menu in Chameleon by pressing the down-arrow button, not SPACE like I said. First, select your partition with left/right-arrows, then press the down-arrow -- you get a menu. Select "Video Info" (navigate with arrow buttons and press enter). You get a list of video modes, you should use one of those as the "Graphics Mode" param, the 1280x720x32 was just an example I gave.
Try both PCIRootUID=0 or PCIRootUID=1 (together with Graphics Mode) -- I'm not exactly sure what it does. 1 works for me, 0 does not.
However, judging by your latter post, your problems might be more complex than mine.
I was able to figure things out, got a mostly working system now. I need the NullCPUPowerManagement kext (in MB: Drivers - Misc), otherwise I get a kernel panic. It used to be part of the MultiBeast preset (pretty sure?), I wonder why not anymore. I'm also using a DSDT, but it doesn't seem to matter at all if I use it or not.
I noticed that we have the same graphics card, here's my full org.chameleon.Boot.plist in case you wanna take a look:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>EthernetBuiltIn</key>
<string>Yes</string>
<key>GraphicsEnabler</key>
<string>Yes</string>
<key>IGPEnabler</key>
<string>No</string>
<key>Kernel</key>
<string>mach_kernel</string>
<key>Kernel Flags</key>
<string> PCIRootUID=1</string>
<key>Legacy Logo</key>
<string>Yes</string>
<key>Timeout</key>
<string>2</string>
<key>Graphics Mode</key>
<string>"1280x720x32"</string>
<key>GenerateCStates</key>
<string>Yes</string>
<key>GeneratePStates</key>
<string>Yes</string>
<key>UseKernelCache</key>
<string>Yes</string>
</dict>
</plist>
PS: When you install kexts, better boot with -f afterwards, I think it flushes the kext cache (or whatever). It takes longer to boot, but are less likely to run into problems. You can also use Kext Wizard for rebuilding the kext cache. In general, it's safer to boot with -f.
