For some reason I can't get this to work on "The Spectrum" using the original ROMs. Just crashes out for me.
Viewing post in Santa's Lost & Found comments
I've just updated mine to 1.03 and it still works fine, so I'm not sure what is going on with yours. I've tried with and without the 48.rom, with and without extended colours, can't think of any other setting to try to see what might be causing it. Have you tried a factory reset?
EDIT: PS. make sure to try the latest version from here, so we're testing exactly the same version.