gpSP fix
While I don't provide explicit support and wouldn't really enjoy playing rijonAdventures on a PSP's GBA emulator, it's good to provide support for people who want to do the job.
I've received complaints that people have been unable to save the game as there's been a modification made to the game code (but not the saving mechanism). The save menu does not work, and saving via gpSP's save states is not efficient.
Nonetheless, it's quite easy to fix.
The gpSP app folder in the PSP's GAME folder contains a file called game_config.txt. In order to save, the following entry needs to be appended at the end of this text file:
# Pokemon: rijonAdventures
game_name = RIJON ADVENT
game_code = BPRE
vender_code = 01
idle_loop_eliminate_target = 080008c6
flash_rom_type = 128KB
Special thanks to Dabomstew at The PokéCommunity for providing an insight into doing this correctly.