I had another look at that page and some progress was made. Now my wireless xbox 360 controller connect as player 2 (indicated by light on controller) works except for the left and right trigger buttons. However, it is only player 2 that works; no others. I think it might be because my emu.cfg inputs are jacked:

[input]
evdev_device_id_1 = 5
evdev_device_id_2 = 6
evdev_device_id_3 = 7
evdev_device_id_4 = -1
evdev_mapping_1 = /opt/retropie/configs/dreamcast/mappings/controller_XboxGamepad(userspacedriver)#2.cfg
evdev_mapping_2 = /opt/retropie/configs/dreamcast/mappings/controller_XboxGamepad(userspacedriver)#3.cfg
evdev_mapping_3 = /opt/retropie/configs/dreamcast/mappings/controller_XboxGamepad(userspacedriver)#4.cfg
joystick_device_id = -1

Doesn’t even seem like controller 1 is even listed here. I tried to change something in this emu.cfg file but when i boot it just reverts back to original and all changes that were made disappear.

So now my question is 1)How can i get my left and right back trigger buttons to work on the one working controller. 2)How can i get controllers connected as players 1,3,4 to work?

Thank you again for your help. You have been great so far.