After playing with this for a while I’ve now been able to successfully derive from ALyraPawn to make my own AMyPawn.
It turns out that ALyraPawn does not implement gameplay ability system, gameplay cues or gameplay tags. All of that logic was put into ALyraCharacter instead, so it’s impossible to use Lyra for a non-character-based game without recreating the wheel.
In order to make AMyPawn that implements these features, I had to forcefully expose a number of Lyra classes and interfaces.
Given this experience I’m guessing this lack of exposure is just an oversight, as was the implementation of all this code into ALyraCharacter rather than ALyraPawn? 