As I understand, ripping a PSF from scratch requires disassembly tools for guidance and tests. I can cheat a bit. I can just take a PSF from Chrono Cross or another game that uses that music engine and insert the music data from the demo. Not entirely authentic, but it should work well enough for playing the music. Each song in Chrono Cross has its own set of instruments, so don't worry about missing out on the different samples if we do it this way. Note that since Beginning of a Dream is part of a video, you can't rip a PSF of it.
If you have extracts of the music data, some instructions for modifying an existing Chrono Cross PSF:
- Get a copy of PSFLab
- Open a Chrono Cross PSF in PSFLab
- Go to File->Import Binary Data
- Select the sequence data and enter in 0x100000 for the destination address
- Repeat steps 3 and 4, but with the instrument data and the address 0x120000