to 1
You have your Monitors A set to lets say analog out 1/2.
Now Mute your Monitors in the Control Room section by clicking "M" besides the fader.
Now you can toggle all mutes to become active/inactive with the main button in the upper right.
to 2 you can play what you want
Easiest is to use the so called "submix mode".
When you click then to an output then you change all the input and playback channels for this only output.
This way you make your way through your outputs to get the mix that you want for this output.
to 3 .. if you assign output channels to Monitor a or b, then they become automatically stereo it appears to me.
Workaround would be to not assign them monitor B and instead of this change them to mono and make then your routing for the mono channels.
BTW there are nice training videos for Totalmix out there ...
http://www.tonstudio-forum.de/blog/inde … al-Videos/
BR Ramses - UFX III, 12Mic, XTC, ADI-2 Pro FS R BE, RayDAT, X10SRi-F, E5-1680v4, Win10Pro22H2, Cub14