1) It's an AMD Athlon II X2 250, running on an ECS-A780LM-M2 motherboard, with 8 GB RAM (2x4GB 1066 kingston), booting from an USB device (yeah, i have a complete 10.8 installation on my USB stick just in case my 10.8.1 netbook suddenly fails on me);
2) Yup, Mountain Lion 10.8.0;
3) I'm using this one, upload by you (and renamed by me):
http://www.xup.in/dl,21183920/universal_kernel.zip/
4) No, no instant reboot at all! A lot of messages like "Symbol not found" or something, much like when i tried to run 10.7.2 with your kernel (yes, i did it, but 10.7.2 actually boot to the desktop), then these lines "failed kext" and "mach0 is malformed", then KP.
I will upload a video of the entire process later, if you think it's useful.
P.S.: i used the following flags: raw64bit (my name for your kernel) npci=0x3000 arch=x86_64 -v
Here's the org.chameleon.plist of my USB 10.8.0, if needed:
<key>Boot Graphics</key>
<string>Yes</string>
<key>Default Partition</key>
<string>hd(0,3)</string>
<key>EthernetBuiltIn</key>
<string>Yes</string>
<key>GenerateCStates</key>
<string>Yes</string>
<key>GeneratePStates</key>
<string>Yes</string>
<key>GraphicsEnabler</key>
<string>Yes</string>
<key>Kernel</key>
<string>custom</string>
<key>Kernel Flags</key>
<string></string>
<key>Quiet Boot</key>
<string>No</string>
<key>Timeout</key>
<string>5</string>
<key>UseKernelCache</key>
<string>No</string>
<key>npci</key>
<string>0x2000</string>
(notice it does not include the bootflags i used)