Cheat Engine is open source and actively developed, you could give that a try for RAM editing/searching, breakpoints, disassembly, and maybe logging.https://cheatengine.org/downloads.php
PS1 games - and all systems that use CDs and probably DVDs - differ from other systems in that you need to deal with the disc image to insert/export files and get it running on real hardware and more accurate emulators. Thankfully much of this is automated with tools like CD Mage, ECCRegen, and PSXImager. If you're having trouble getting something to run, always try to fix the EDC/ECC.
It wouldn't hurt to open up a disc image in a hex editor, read documentation on how sectors work and what directory sectors are, and scroll through it to see for yourself.