Min/Max values for Scalability settings

The only thing I can find for scalability settings is on the Scalability Reference

But there’s nothing explaining each individual setting and what it’s Min/Max value is. I just assume that the values that they’re set to on Epic settings are their max values.

For some options there are only 0 and -1… like ‘r.BlurGBuffer’ in the post processing stuff. Can it be a positive number? only 0 or -1?

Some options ask for resolutions. Do they have to be a power of 2? do they have a min and max value?

Is there a doc somewhere that explains these things?

Also, I have made a button in my options to Auto Detect Scalability settings with the “Scalability auto” command. Is there any way I can get access to what those settings are so I can display them in my options?