An interesting idea and cute implementation. Although I'm not a big fan of JSW style, (however enjoy Panama Joe) but you seem to have realized a few good tricks, including build-in fx/music, smooth elevators and 'level-morphing'.
Yet I think you could do even more, but as I understand, you've already had to use a packer, so I guess it is hight time to ask our Jonathan to implement some level save/loading or just do it ourselves, because all the gamedata is available even after gameend.
BTW, did you used compiled code to add to the game? E.g. asm X's.
Thank you for your attention to the game. I've been thinking about it .. Maybe Jonathan will do so in a different version agd .. we only hope .. Now I have an idea, make a big play .., several code blocks, all together ...