Ok, yes it locks after the first level, when it does IO to load something.
The IO-patch (to simulate disk-access) from atarimax seems to be running from stack and partly erased during the game, causing the crash.
So I don't think it will work.
Beside that, I thought there was an option somewhere to move the XEX-loader in memory to a known safe place.
But I couldn't find that in the MaxFash Studio 2.14 I am running.
Anyhow, I tried it on LiteDOS, that works and it fits on a single sided single density disk.
Grtz,
Sijmen.