Comments

I can't seem to move forward in the ZX Spectrum version?

I had something similar in the CPC version which just Freezes.

What is the command line to run the coco3 version?

Attach the disk and type

RUN "LOADER

Then type `RUN` at the ugBASIC prompt.

Unfortunately the CPC DSK image isn't working for CPCBox:

returning: "[DSK Parser] Error: Invalid DSK id"

very good

Beyond the Door (Various 8 Bit Computers) by spotlessmind1975