Unfortunately I could not replicate this issue, I set up the settings as mentioned,  play HoG 4 and shields worked properly. I saved then load. And shield still worked as intended.

If you do have the issue happen again, feel free to reopen this ticket, but we'll need you to supply a game log and a save file please ?

Thank you !

I'm terribly sorry that this happened, but I could not replicate the issue even after mixing save and load at different stage of the fight. If we find a replicable step with which I can see the bug myself, I'm happy to reopen the ticket and have another look. But at this stage I don't know what went wrong that could have corrupted the file / game state