Setting Offset for GoFlight LEDs

This is my very first attempt to work with GFdisplay, FSUIPC, and offsets. Try as I might to make sense of the documentation and explanations for GFdisplay and FSUIPC, it remains beyond my grasp to implement. So any tutoring on my behalf would be most appreciated.

I have successfully used FSUIPC to set the far-right button on my GF-166 (NAV1) to toggle on/off MARKER IDENT. In GFConfig, I have chosen NO SELECTION for that particular button.

Now I want to simply make the respective LED (L2?) on the GF-166 light up whenever the MARKER IDENT is engaged.

Could someone, please, provide me with a little direction and help me make sense of the offset settings necessary to make this work?