Marcus,
I'm really happy to see the progress you have made with extending MY-BASIC. Even though I wish you were doing this in SDL so it could be ported to Android, seeing how you extended MY-BASIC will be worth its weight in gold anyway.
Can you run the Mandlebrot again and wait to do the sync until the end? Updating the canvas with every pixel is painful in any language.
It would be great if you could join us on All BASIC and collaborate with the 12 other BASIC developers that are members there.
John