So I read somewhere that it's possible for me to save an isolated version of an older KSP and then be able to have the newer KSP and I was wondering how one goes about doing that. I have KSP 0.25 on Steam still because I have it set to where it loads the [Previous] version so that it doesn't upgrade to "BETA Than Ever" due to the fact that a number of the mods that I have for 0.25 have not been updated to 0.90 and a few of them most likely never will, (like modular multiwheels.) I'd like to be able to keep my 0.25 available to play at any time but then, at different points, hop onto 0.90 Beta without the fear of losing crafts that I'll never be able to remake in 0.90 due to mod compatibility.