First, I love this Mod. Thanks for your time!
When spawning custom log, timber piles and pallets, using a custom.json file, the mod does not seem to be picking them up.

I'm not a C dev, so please have mercy!

In your LumberYardScriptsClass.c file, you seem to be extending:
class Static_Misc_Pallets3: z_LumberPile_Base_Static
and returning, Static_Misc_Pallets3 but I'm calling --StaticObj_Misc_Pallets3-- in the custom json file, to get the large stack of pallets to spawn. I don't know if this has anything to do with the issue or not.

But it seems like you are also searching for anything with the phrase, "pallet"

So, when I call StaticObj_Misc_Pallets3, shouldn't it pick it up?