Since the last patch I seem to no longer be able to assign ability to hotkeys. My guess is that it has to do with the fact that I'm using a keyboard with an AZERTY layout.

I reassigned the hotbar buttons to & é " ' ( - but in the ability wheel, the game still considers that the keys for the hotbar should be 1 2 3 4 5 6. Since these keys technically don't exist on an AZERTY keyboard I'm not able to assign abilities from the ability wheel to the hotbar.

Hello, 

I found a solution to your problem.
I had exactly the same one, and couldn(t change my spells slot.
To change them, i changed my keyboard (AZERTY) into a QWERTY one 
Not physically of course, i changed the settings in Windows to add a keyboard. Back in game, assigned the spell, than went back into AZERTY.

Hope that will help you !