How do I downgrade using SteamCMD

Hello. I know there is a way to download an earlier version of starbound but I don't know how to use the steam depot downloader or SteamCMD. Could anybody help me? I'd like to convert my old game safe to the new version of starbound with starcheat (yes I know there will be bugged items but i dont care bout that) but that only works if I have an older version of starbound (preferably Glad Giraffe 0.27.1)
Could anybody help me out or maybe even have an old zipped glad giraffe game?