After some discussion at worldofspectrum, I learned that the problem with Fuse PSP is psplib’s restrictive disclaimer, which prohibited commercial use of the code. psplib is the library that I initially wrote for fMSX PSP; it is common to all the ports I’ve done to date. While the disclaimer wasn’t actually meant to serve as a legal document (as I mentioned in the forum, I’ve always considered psplib public domain software), Philip’s argument is that it went against GPL, which prohibits user restrictions.
To resolve this incompatibility, I’ve decided to license psplib under the GPL. The library is already undergoing structural changes (parts of it have needed tweaks for a while now), so now seems as good a time as any. The updated library is in the trunk branch of Fuse PSP’s repository.
Fuse PSP binaries are once again downloadable.
I'm a programmer with too much interest in too many programming languages, and not enough time.