DraStic

Title says it all. I don't get the option to set controls for the shield in the external controller settings (map controls is grayed out). To make sure it isn't just my controller, I confirmed that the controller is properly detected in the following other programs:

ePSXe
SuperGNES
Retroarche

Appreciate the help!

In the External Controller menu:
Select Key Mapping -> any of the "No Mapping"

then tap map control and it should then detect your controller and automatically enter it's name in place of "No Mapping"

Thanks! That took care of the issue. One problem that remains is that it does not detect the trigger buttons on the shield (which are detected in other emulators and bindable). Any thoughts on what the problem might be?

Check "Enable Analog Triggers". They should be mapped to L and R automatically, not sure if they can be changed.