Can navigate retropie menus but no controls in game? xinmotek+RetroPie4.6

[cmdcolin]

I have a Raspberry Pi 2, I reformatted the microSD and installed RetroPie4.6 on it
I am using an official power supply m052240w111
I am connecting a xinmotek xm10 and a USB drive for the ROMs that is freshly formatted
During initial retropie setup I configured a "start" button, an "A" button and directional joystick
I am not receiving any errors or anything, but I am not getting any buttons to work in the game even though I can navigate the menus of the retropie with the xinmotek
I have the mame2003 emulator setup and am doing arcade games. Haven't tried other games at this time, but attempted bombjack and galaga (both not working yet)
On game startup, the game plays and looks fine and has noises but my button presses do not start the game. On initial game startup it has a blurb in the lower left corner saying that xinmotek is the #0 controller

I would love any tips, it seems like I'm so close but I don't know what is wrong :) I can also connect a keyboard and do f4, enter command prompt, etc, if any more info is helpful. I have seen other entries on the forum that seem related but didn't gather any next steps from them

[cmdcolin]

I also attempted to setup the keyboard as a controller too, and sort of same thing, can't get controls to work on the game

[cmdcolin]

I tried a super mario bros SNES and I think it is working better and I have some controls. I wonder why don't these arcade game controls work though?

[cmdcolin]

I think the key was I needed to configure a SELECT (or maybe the HOTKEY which gets auto mapped to select)

Since I have a limited set of buttons I thought just having A and START configured was sufficient but adding a SELECT key helped

[mitu]

@cmdcolin Select is mapped by default to 'Coin Insert' in arcade emulators. Without it, you wouldn't be able to start a game.