Hi Marian,
There is a mistake in the manual on that radio and you are correct, you will need to manually go into Flap Trim and uninhibit it. It will not automatically come on just by making Flaperon active.
You will not lose any settings by removing the NiCd battery from your transmitter, please see our FAQ:
http://www.futaba-rc.com/faq/service-faq.html#q272.
I hope you find this information helpful. You can also reach our Futaba support technical team at 217-398-8970, or via fax at 217-398-7721.
Sincerely,
Krysta
Lead Futaba Customer Service and Programming Technician
Also you may want to check our Website at (
http://www.futaba-rc.com)