I'm pretty sure the sequel was announced and subsequently cancelled. You can chalk that up to poor performance most likely. Also in 2006 the GBA was obsolete and out the door. I'm not sure how well the GT anime was doing in the states at the time but I guess not well enough to warrant more games.
Transformation really ought to have remained in the Legacy of Goku styling.
Still, two great games, one average/mixed, two god awful ones. That's Webfoot's track record on GBA.
Dragon Ball GT: Episodes 11 - 15
I think they managed to bounce back here. Dolltaki is such a weird and interesting character. He reminds me of Salad Fingers. The Luud fight was long and boring and I can't understand why the two wouldn't just go all out as Super Saiyan, outside of plot...
Well I watched it in 1080p on a 27 inch monitor and I only have very mild astigmatism so I don't think that's it. I've never had a problem with any of the other films really.