Yes I know. I have done that and it works fine with all my new registratons. The problem is the old one from Tyros 5. But I am working on it and save them over again with activated assignable button.
Take care
Ingar
Once you assign a button, it stays that way (unless changed by a registration). But none of your T5 registrations will change assignments because they never knew about assignments in the first place.
Sounds to me like your problem is "save them over again". By saving them, you’re introducing the ability for them to change your assignments. Quit doing that.
I would reload all your T5 registrations. I bet they work fine, and leave your assignments alone.
Cheers,
Fred