People have already told you the solution. Opt out of the experimental branch. I understand you don't like that idea but that honestly is the solution. The devs are unlikely to support multiple versions of the experimental branch because they need everyone who is opted in to play on the latest version so they can find bugs and provide feedback. You can also turn off temperate/oxygen consumption in your save game's difficulty settings in the meantime until they get the pressurization bug fixed. There are multiple solutions to your problem and while they may not be the one that you want, they are there to use if you want.