#1
I'm just wondering if I need to pick up speaker cable, or if I can send the amplified signal from my amp to my cab via a standard mic/instrument cable.

It's for recording purposes, so I want to have the amp in the control room and send the signal through my patchbay into my live room, but I don't want to break anything or start any fires.
#2
Speaker cable, definitely. Especially over long runs. Instrument cable isn't meant to handle the higher current and the conductor may burn out, which can mess up your amp in a hurry.
#6
Yeah, there's no point in using my patchbay anyways, as I could only send it out a standard mic cable with the way I have it set up. I have an old semi-plugged hole from before I set up my snake that I can use to run a speaker cable.