1. yep, easy, when you click on midi mapping you have three buttons at the top of the main window, Focus, Position and Layerset + Position - click position then you can select wach layer to be effected by a different midi control for opacity
2. similar to above if I remember rightly, have't done this though
3. not at mo, aparently for version 3
4. dunno, sure someone else will
5. yep, theres a module that does this, sorry not at my Modul8 machine at mo and can't remember what its called....