Hi! Is it totally necessary to run FES in Unity version 2017.1.1? I'm trying to make it run on 2017.3.1f1 and I get this error: "Input Axis P1_VERTICAL is not setup".
No, RetroBlit will run on any version starting 2017.1.1. It sounds like your input settings have changed, RetroBlit is a complete project, you should let it keep it's own configuration after you import it.
Feel free to email at the support email address if you're still having trouble!