The actual API is called through Python. But it is oriented towards querying an existing GEMINI database. I don't think you can currently run GEMINI on a Windows platform. My suggestion would be to either install and use Linux on a machine (or dual-boot) or, if GEMINI is the only thing you want to use, to set up a virtual machine of some sort. This can be Linux installed inside Virtualbox or you can set up something like Vagrant which is lighter weight and will basically just give you a command-line install of Linux to work with.