I just happened to run into Anthony Madden (@ChiGamesStudio) on Twitter today and he was working on something very cool. He has made an SDK for AltSpaceVR using Unity3d. For the bonus round, he has made it available for developers! You can pick up the early release here *updated* (New Github link).
I highly recommend checking out this tutorial that Anthony has put together for the SDK.
Give him a follow on twitter and sub his channel for more info.