Having trouble configuring Buttons for my Retropie Arcade

Hello! For a class project, I decided to make my own arcade. I have played with Retropie successfully in the past, being able to play SNES, NES, GB, and GBC with a USB SNES controller. Now I have a 2 player setup of Joystick and buttons (Images linked below). I am very confused on how to set them up. They all light up and are recognized by the configuration setup. All of the reviews say that the Pi “recognized them instantly” and “it was super easy, no problems”.

When the Pi is booted, I am prompted with a configuration screen for Xbox 360-like buttons, and it is only asking for one controller to be set up.

What Controls should be what for what game/s, or what could get me closer to knowing that? Here is a list of games that I installed http://bit.ly/2scXkoB and I got them from here http://bit.ly/2rg2DnJ

How do I properly load and save control configurations?

How do I get the second set of controls to function?

How to I get the shortcuts, particularly start+select to exit games?

Why do most of my games crash or are not recognized?

Even if I configure a SNES-like set of controls, why wont the SNES games respond to button presses?

I would be happy even if it turns out that I can’t play MAME games, just NES and SNES would be fine with me if it had to come down to it.

I have the EasyGet DIY 2 Player Red and Blue Arcade Kit from Amazon.
https://www.amazon.com/Easyget-Encoder-J…B00WAY9848
http://imgur.com/1kE2ina
http://imgur.com/aC1xhcX
http://imgur.com/9TTWu3q