I created a little patcher that enables the hidden themes for Rockford (1988) by Mastertronic, as well as some kind of reconstructions of their graphic sets (scuba diver, football player, musician, leprechaun and miner).
The patcher is written in Python and does the following things: makes a new exe file called addon.exe that uses my (rather) primitive reconstructions of the missing themes, and modifies the cellmaps.bin and the exe to use new graphics sets, and the correct times / gold counts for each level. I also made a tool for converting between planar EGA and PNG, and normalized the palettes for the hidden themes in a way that they use the EGA color space instead of poor conversions from Amiga OCS palettes that miss out several colors.
Here is a little showcase of the project:
https://www.youtube.com/watch?v=NGcIWHs7anc
And here is the patcher with longish background:
https://github.com/asahala/Rockford-Patcher
If someone is interested in collaboration, let me know. I'd need help with adjusting some of the graphics (in case you are a pixel artist and good at mimicking the original Rockford style). I have not drawn the death/win/time out animations, so that would be great too.