Have you looked at the compatibility list of dios mios and seen that phantasy star online appears to work. Only to look up countless tuts and follow directions perfectly but somehow that game still doesn't work? I know this is my first post, but i felt that this was needed, i've tried this on...
But Nintendo's GBA video format is different, being that it uses a custom ROM and chipset for rendering, for like the Shrek and Shark Tale titles. Been undumpable for years and years.