It appears that when not directly referenced by a component in the scene, Scene/Singleton Class definitions don't instantiate themselves.
In my case, I have a Scene Class that's (in theory) always doing some calculations and applying the results to various Asset Classes. Even though components in my scene use those assets, the scene won't instantiate itself, and thus it wont do its calculations.
My current work around is to send a shared event to everything on load, forcing them to spawn.
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