How about adding support for partial brush in collision detection function?
I'm currently writing a little three layer parallax scrolling platform game, just for kicks. I need to use double buffer for drawing and sprite frames are vertically aligned in a brush. It's simple to draw sprites and do sprite animation with a couple of table lookups and by drawing sprites using DisplayBrushPart().
Currently, I use collision points and boxes with sprites and collision map with level, and do collision detection by myself. If I would want to use in-built collision detection function for pixel perfect collision detection, I would first need to copy brush, crop the current sprite frame from that brush and then use that cropped brush with the collision detection function.
By the way I think Hollywood is great! With just about a little over two hours of work I now have a three layer parallax scrolling Super Mario clone with collectable coins and working enemies done.