One thing you can do is download a copy of the process whenever you want to "save a version". You can continue to make changes to the process and keep downloading to retain that version. If you ever want to go back to a previous version, you can import that and overwrite the current process. 

If you have Rio or subscription with multiple Forms servers, you can do this even better with prod and dev environments. You have your process in the prod Forms server, and you can download that and import into your dev environment. Make changes and test them there, then download and bring the updated copy back to production. On import, it will recognize this process originally came from production and ask if you want to overwrite the existing process. That way you keep all your history + data while keeping a copy of each version of the process.