I just wanted to post about OBS, but I see you already did
Some additional info:
It works fine on Linux for me, but in the sources part I have to select screen capture, window capture doesn't work.
So my method is:
start sauer (with sdlhack, so you can alt+tab, see the relevant topic)
start obs, configure it for screen capture
start capture, switch to sauer
Some tips for performance:
I have intel core 2 quad @ 2.93ghz quadcore, nvidia gt660 and play at 1920x1080 res.
First i tried to record to my data storage hdd (western digital green, slow) at 1080p 30fps but sauer was unplayable and the video was very bad but also high file size. I changed the config to 1280x720 (not the game but only in obs so it downscales), and instead of the hdd I recorded to my ssd. I get very good quality video and about 20megabytes/1 minute filesize, and can play sauer at 100-200 fps while recording. (Now I realized that other stuff was running from the data storage hdd so that maybe the cause of the problem)
So if you have perforamnce or quality issues:
-try with 30 fps if you set higher (not really worth it to go lower in my opinion)
-lower resolution in obs (1280x720 still looks good)
-check if your hdd is too slow or overused (can't keep up with writing the video)
in conclusion, obs is very good for recording sauer gameplay, recommended
