not being shown in outliner I’ve never seen, but issues with HUD/UMG and PlayerController I’ve seen.
There’s a bug that at that point things may not be initialised, can you try adding a Delay of like 0.1s before creating UMG widget? Let me know if errors go away.
That’s how I was told to do it by Epic for now to get around issue.
Regards,
Nuno Afonso