I don't think you've made MyDocs executable mate, do other games run from there?

If you haven't tried other games easiest way to check is to go back into

/usr/sbin/mmc-mount

and make sure 'no-exec' has been taken out and the fmask value has been changed from 0133 to 000, if they show up as they were when you go back in then you've not saved the changes properly on exit... which is easily done.

Alternatively just install Maemodder, and press 'Make MyDocs Executable' which will guarantee it's done right

Kind Regards,
D4rKlar