In what way did it crash? What browser and device did you try running it on? - There might be an issue where its possible to start typing before the program load sequence has finished, e.g. where it has queued a "RUN" command for when the disk load has finished, but if you start typing before that, it might interfere with that RUN. I have an idea on how to fix that, if this is the issue. Just need to ignore key presses until all program load commands have been processed.