midd

Me and Eric Ramirez put these AHK scripts together for our Stream decks.  We have available:
Load State, Save State, Next Shader, Previous Shader.   Menu, Exit, Pause, Fast Forward, Rewind, Cheats
 
They are hot key functions utilizing 5 as the hot key.  You can make the hot key anything you want but you'll have to edit each script.  Same thing with the key to activate the function.  For example 5 and the space bar will fast forward your game.  Go to Retroarch-Settings-Input to check those assigned keys to the listed functions.
 
Just create a profile (I called mine Retroarch). Point it to your Retroarch.exe file.   To assign functions, go down to System and drag the Open Icon to one of the windows. Choose a script and give it a name. That's all there is to it. 

Put a wheel on your spinner and race away!

A playlist for arcade games that used 2 sticks.

For games that utilize your trackball.  Multi-platform

For games that utilize your spinner.