While the overall condition of the camera is pretty awful, the idea of a removable back panel like that is interesting. I think with careful machining it could be done very well. The workmanship would have to be very good to avoid light leaks. I seem to remember some ridiculous-looking black and orange Russian Barnack copies on ebay with a feature like that. Now if they could just make a straight modified Zorki without the Hallowe'en colour scheme and all the phony German insignia, they could have an interesting product.
Cheers,
Dez