Is this Windows XP? It's really helpful if you do have some DirectRT sessions that will run on the laptop. The first thing I would do is compare the style files for a session that does work and one that doesn't. Do you see style (.drt) files in each of the folders--i.e., within each of one that does work and within the one that doesn't? If so, open the .drt files and compare the screen resolution that is set under "Options". Different?