Im using Xbox One Controller. So your psx controller should work like my controller to.
You have to go into Controller Configuration, then select emulatet wiimote and click on edit or change on the right side. Now you see the screen for button mapping. From here you can select your InputDevice on the left side. Then map the keys like you want it for your spezific game. After mapping you can save this profile on the right upper side. For example name it newsupermariobros1 (for player one). Then i made this again but i selected my next Xbox One Controller as InputDevice and named it newsupermariobros2 and so on.
Set the lines in the .ini file and it should work.
Some profiles can be used for more games. I use my newsupermariobros-configuration for all games with wiimote-sideways. Then i have one more profile for wiimote with nunchuck(games like supermariogalaxy, zelda, etc.). You can map the shaking feature on buttons.