@dankcushions Alright thank you already! I do know it's possible to wire it like that but im more worried to how some games will respond to it when trying to play solo. I guess I will keep it simple for my first build and just use 2 separate ones.

Thanks guys! This worked for me as well.
I don't update regularly, but once I did, I found same issue with my Multitap settings set to "auto", leaving my Castlevania Symphony of the Night quest on hold till I figured it out :)

@KLAJD Did you enable the Kiosk UI mode from EmulationStation's menu ?

It worked! Unbelievable. That is absolutely amazing. Thank you, @mitu !

After not being able to find an answer anywhere I decided to reformat the sd card and do a fresh install with a nespi+ case that I was using before and the same os 4.5.1 and 3b+ pi. I have however run into the following issues.

I have just recently had to reformat and reinstall retropie 4.5.1 on my 3b+ with nespi+ case. Installed the image and the safe shutdown script but for some reason the power button isn't working on the case. If I push it in to turn on the case nothing happens but if I push it again to make it come out the pi boots up but there is of course no power light.

The pi won't power off with the button and the reset button seems to not work at all. I am not sure why this is happening as its a fresh install and previous to the reformatting the case and buttons installed and worked without issue. Any help would be appreciated.

Got it resolved by editing /etc/modprobe.d/xpad.conf and changing triggers_to_buttons to 0

@Mebejedi Well, in lr-mame2010, after you insert a coin, the screen is cleared of the demo, then you can move the ship at the top left or right and fire depth charges left or right, while a sonar sound effect is played and submarines move about below.

@Shane1 That's not really a RetroPie related question, but more of a programming/hardware question about your controller and how it should be set-up.
Is your controller identified as a gamepad by Emulationstation in the input configuration dialog ? How did you set it up - what configuration have to done in Raspbian to get it recognized ?
Can you give more details about the controller hardware and how it's connected to the PI, etc.

@DaMota What games, who are 'they' ? Please add some context to your problem as directed in https://retropie.org.uk/forum/topic/3/read-this-first. Have you mapped your buttons correctly in Emulationstation ? What game/emulator, etc.

I went through controller setup again. This time I made the XBox button my Hotkey. Now I can start games by pressing Start and Right Trigger and I can exit a game to the main menu by pressing XBox button and Start. The Start button by itself, however, does nothing.

I should mention that the Start button works by itself flawlessly as you would expect from within Emulation Station to bring up the main menu. It's only within the actual games themselves that I have to use the weird Start/Right Trigger combination.

Any ideas?

Thanks guys - that sorted it. No idea what config files I've been finding and deleting until now, but that first location had the default.cfg and tons of seperate game ones too. Wiped them all, rebooted and mame seems to be fine now.

Many thanks for your contributions. Case solved!

~Z~

@g6delta No problem, I hope it solved your problem

@richiegigabit Yeah or the Alpha series. :-)

@juan19802005 if you don't even know which emulator you're using and what configs you've changed I'd suggest going back to the docs and giving them a read.

https://retropie.org.uk/docs/First-Installation/

https://retropie.org.uk/docs/Controller-Configuration/

And if you're modifying retroarch configs

https://retropie.org.uk/docs/RetroArch-Configuration/