Welcome obe1,
Are you referring to viewport specific overide of default layer color?
The general characteristics of any paperspace viewport are changed by double-clicking on the viewport border entity (make sure that it is not on a hidden layer) - just like editing any other entity in progeCAD.
There are also some viewport specific commands like
VPLAYER for controlling per-viewport layer visibility, I am just not sure exactly yet what kind of "overides" that you are looking for..