I managed to release Minimum Damage today, and only a couple of days late! I'm actually really happy with the end result: pretty much everything is amateurish, crass and probably broken, but unlike my other games it looks intentional.
This is the first time I've created music for a jam game, but it's been a hugely positive experience. In particular I found it a real relief to work on the music, and get away from the screen (or at least, the IDE) for a while. I've found - like with graphics - that having some concrete assets, no matter how tacky, in place really motivates me in the soul-crushing twilight that is the end stage of game jams. It also took the game in more imaginative directions than I think it could have gone otherwise.
In addition to the music, I'm quite happy with the original idea. For one thing the graphics were simple enough that I could implement them very quickly, allowing time to think about more important things. The execution is imperfect, but maybe I can work that out at a later stage.
So thanks, @Tijn, for hosting this jam! I certainly learned something.