Yes, the colours have to be solid for the masking to work as it should. So padding or diffusion on a single island like this leads to errors as the texture bleeds onto itself.
thats nice. it workes out quite well. also good that you mentioned it with the diffusion and the padding because otherwise i'll get no "full" colors and have some bad errors by selection the different colors.
Oh, you have access to Painter aswell? :) Well in that case , here's another solution: Assign your multi-sub material in Max to your HIGH-poly Now set up your high and low in SP and bake your ID map. In the ID map options make sure to change Vertex Colours to Material Colours from the Colour Source dropdown. Also, as…