Yamaha released in the mean time a firmware update V1.13 for the Tyros 5 that should solve this issue.
When the iPad with iOS 10 is connected with the WiFi stick to the Tyros 5 using "Access Point Mode" in Tyros, then the remote control for registrations doesn't work anymore and SongBook+ may even hang on start.
A customer found now a workaround for this issue. Thank you very much for sharing the solution with us!
Change in the WiFi settings of iPad for the conneciton with Tyros from DHCP to Static IP address.
If the iPad is the only device connected to the Tyros network, you can use 192.168.0.2 as IP address, otherwise use a higher IP address like 192.168.1.100. DNS should be set empty or 0, Router should be 192.168.0.1.
Does that help also for you?
Yamaha is informed and has confirmed the misbehavior.
The workaround above can be used as temporary solution.