It should not take a "ridiculous amount of torque" to open up the pad spacing to fit over the rotor. First of all, before you place the new pads you should ensure that the piston is pushed back into the cylinder of the caliper so that it's flush (or nearly flush depending on the design) with the surface of the caliper.
How you push the piston in ...
This is the brake fluid tank. Underneath it likely has the ABS actuators, which likely make the sound you are hearing. I'd start by diagnosing ABS (with a scanner). If you don't have the scanner that can diagnose ABS - pull the ABS fuse and start the car to see if the sound is still there.
A red ABS warning light has no different meaning from an orange or yellow warning light.
The warninght light can turn on for a few reasons:
One or more wheel speed sensors have failed
One or more wheel speed sensors are covered with road grime
One or more wheel speed sensors are unreachable (broken wire)
A blown fuse for the system
The ABS module is not ...