For some reason, casting was failing yesterday, but doing it today it works just fine. I think the problem was I was trying to cast to the child individually (get child at index) when I needed to Get All Children and perform a for-loop from the array.
Some of the casting with UMG is so strange… I can’t resize the uniform grid or move slots. If I remove an entry, the empty space stays there. The system wants to add, it doesn’t want to change.