first of all, the skin is a global parameter, so if you choose nebula reverb for example, it will always have the chosen skin ( i don't know why changing and saving in mastpage doesn't keep it, here it works).
but you could copy the nebula dll and xml, and give it a new name (the same obviously ). this way you can have different skins, for different tasks.
system 1: windows 8 32 bit - samplitude prox, tracktion6, reaper system 2: mac osx yosemite - reaper(32+64bit), tracktion6(32+64bit)
both systems on: macbook pro (late 2009), core 2 duo 3,06 ghz, 4 gb ram, graphic: nvidia geforce 9600M GT 512 MB