It's probably a couple of months of intermittently using £15pm subscriptions between OpenAI, Anthropic and Google; nowhere near maxing them out.
MSC 5.1 is a relatively simple compiler; and there's lots of prior art on Civ 1. I've set them off on a slightly more obscure and recent game now; so we'll see how well they manage on that!
Regarding legality - IANAL so perhaps we'll see. I just wanted to see how the sausage was made.
Interestingly; the way that MSC51 and LINK 5 lay out the binary depends on identifier names. There's also length restrictions due to memory limitations. So although the names aren't going to be historically accurate; the possibilities are at least bounded!