Are there instructions available on how to back up a PS1 game, which is NOT already dumped, using a MacOS computer?

DiscImageCreator (one of the two "official" dumping tools) apparently supports macOS, and apparently so does Redumper (the other "official" tool); however the GUI front-end for both (MPF) is Windows-only. You can find the dumping guide for the CLI version of DiscImageCreator on the wiki, for Redumper the GitHub README page does a good job explaining how to use it. Sadly, dumping CDs usually requires a Plextor drive, which haven't been manufactured for a while already. You can get good results with the supported LG drives if they're not discs with audio tracks nor protected by SafeDisc, at least from my personal experience with PC games, but I don't know how good it can be for PSX discs.

#1) Are there instructions available on how to back up a PS1 game, which is NOT already dumped, using a MacOS computer?  A friend has an old one-of-a-kind PS1 game that I want to be preserved.  I am a windows user and have ImgBurn.  He is reluctant to send it to me (tbh, I don't want to take the chance of it getting lost in the mail). He sent via google drive a .CDR image of it but although ImgBurn wrote the image, it doesn't work on a PS1 or emulator (and the directory looks odd).  I'm thinking whatever software he used didn't copy the image correctly.  I need to give him simple instructions and make it as painless as possible otherwise he will just keep the disc.

#2) I found source code to an unreleased PS1 game which I thought I lost years ago.  When I first obtained this, the programmer told me that it should work but I don't have the knowledge to compile it.  Is there any interest in someone trying to compile it and getting it to work to preserve?  I assume PS1 dev kits and knowledge of how to use them is very rare these days.

Thank you all!