1.) You mean the 6 wires coming out of the plug? Download the manual from the store. It will tell you. 1 is 12v constant, 12v switched, Ground, Remote Lead, and others are optional I believe.
2.) What the hell do you mean stabalizer. Regulator? No the M1 and M2 do that.
3.)You can power the screen off the ignition if it has a cigarette lighter adaptor. Chop it off and break out the soldering gun. Otherwise use a 12v rail and a ground from the M1. If you use a via board the P4 connector (4pin, on M1 by the ATX connector) gives off 12 volts. Also the yellow line and any black wire on it will be 12v and ground. If you do it that way, chop off the little black box on the cigarette adaptor or it will be uber regulated and not work as efficiently.
4.)Voltage Regulator built into M1
5.) Yes. Does exactly as it says. Car starts, PC starts. Car off, Pc goes off after specified time set by jumpers.
6.)It will do a hard off after a preset time too unless you tell it not too (not recommended). So like pulling the plug. Example. Turn off car, PC hibernates or standby after 30 seconds of no ign power. After 2 hours of not being turned on, it pulls the plug. USB devices are cut too.
7.) Yes, it will fit. Exact same size.
7b.) Not as an option because they have better things to do probably.
8.) Seriously! You do 1 of 2 things.
a - Unplug the M1/M2 from mobo. Take a desktop PSU and plug in the ATX connector. Push On. Voila
b - Take a desktop PSU, chop off a molex and strip the yellow and a black lead. yellow to 12v constant and ignition. Black to ground. Take pin 14 of the desktop PSU's ATX connector (usually green) and ground it to a black wire. Now when power is sent to the PSU, on it goes sending 12volts. M1/M2 thinks it is a car, waits a second or two and powers up.
Now I'm bored so no more spoonfeeding. Search. There is an Ampie thread that answers all of this already anyways. Most important advise: SEARCH!!!!!!!!!!!!