Hmm, I tried the deps package from there and now I'm getting "openxcom.exe has stopped working" on launch.
Sigh. I have a feeling it's yaml. If I replace it with the one I built then it runs, but it still has massive slowdown in the battlescape. It's not FPS slowdown, it stays at 60+fps the whole time, but the animation speeds are almost like they are all set to 1 even though they're at 6, even when using the software mode with no scaler at 640x400.