I tried to config the buttons through the main input config area while retropie was running and found that retropie recognizes the Ultimate OI board by Ultimarc as one game controller. Seems to me it has to be configured through the script manually. I'm trying it tonight to see if I'm successful. Did you ever get yours working @EspenT ?
@mrbouncyballs you might be having the common problem of using an 8-way joystick on a 4-way game. Take a look at your joystick when you are hitting the four cardinal directions. Are you also accidentally hitting two directions at once (effectively a diagonal?). For example, if you push up, it should only actuate the up switch. Does it also sometimes actuate a left or right at the same time? If so, it will be hard to play 4-way games like Dig Dug and Mr. Do because every time you are inadvertently hitting a diagonal (two switches at once) the game does not know what to do. It is impossible for the game to know your intentions, so it often sticks, or misses a turn.
Your joystick, depending on what it is, may have an adjustment, or allow you to flip the actuator around making it harder to hit the diagonals. The actual arcade games use restrictor plates making it impossible to hit a diagonal. That works great on a single game, but isn't very flexible for us who want to play Pac Man (4-way) and then play Gauntlet (8-way). Programmable joystick can help, or a switching restrictor plate, or a separate joystick for each type. The compromise I came to on my system which isn't perfect is setting up my joysticks such that they are 8-way, but that it is hard to get them perfectly in the corner to trigger two switches.
After doing more reasurch I found that my problem is that I need to configure my second player for PiFBA.
This is true and once again, if you read the guide it will tell you how and with what file. Please do not ask any further questions until you have read https://retropie.org.uk/forum/topic/3/read-this-first. It is obvious that you have ignored it despite it being printed at the top of the page and despite agreeing to it when you signed up.