To be clear, that’s Cataclysm:Dark Days Ahead or CDDA. It’s quite removed from the original cataclysm by whalesdev, and is more focused on strict realism. There is also Cataclysm Bright Nights which is closer to the arcadey feel of the original. Both are great and are open source.

Not directly answering your question, but if you haven’t already you should take a look at the end of life disaster recovery repo.

Sunshine and moonlight are open source implementations of nvidia’s game streaming protocol they created for the nvidia shield. You can use it to remotely use your computer from your phone, not just for games. But of course the primary application is game streaming. As long as the game can run on the host (sunshine) computer, you can remotely play it on the client (moonlight) device. I’ve used it to just launch steam in big picture mode and then select what I want from steam.

Lossless Cut FOSS, Crossplatform frontend for ffmpeg. Note that to do it losslessly, it will still be in mp3. If you need to transcode you can do that too, but like others have said you’ll probably lose quality.