All versions of Kawaks behave the same way for me (145, 146, 148d, 150,152,153). Changing the video memory allocation doesn't help, nor does going to full screen. My computer is able to run Nebula, and even MAME (although it takes ten minutes to load a rom). I've never tried FBA. Having run various emus on other computers, I just like Kawaks the best. Oh well. Thanks for the ideas.