Check the “Default Engrams” array in the inventory component and if you want just items empty it. I think every index of the “Default Engrams” array relates to one index in the default inventory items array. If you set the value in the “Default Engrams” array to 0 it spawns the item, if you set it to 1 it adds the engram. By default the first two indexes are set to 1, that might be why you get no items.