Jay,

Like I told you in the accompaning Email I now dont use the BMP variant anymore but the PNG which have a transparant background.
To create MSK objects: I used to do this with goodols Paint.
Open the .BMP file
make everything you want to be as in invert'shadow' solid black and everything else solid white. This file you save with the exactsamename with extension .msk. Take care you must instruct Paint to accept .MSK as a Pain-usable extension, otherwise you will end up with
eaxactsamename.msk.bmp This .msk file needs to be placed in the same directory as your BMP file.
Hope I am clear.
Best regards,
Koen