Couldnt it be done with planes ala you have intersecting planes each with one of the views, then the compter decides which plane faces camera the most, unhides other planes and makes this plane face the camera :S I dont know crap about scripting so you might aswell ignore me here
sounds like a maxscript task to me. you would define your images and then make the script that it runs over the whole animation and computes angle of the "sprite" object towards camera, decomposing that vector into euler rot or polar coords, you would make a lookup in your imagelist and set that as active map of the…