Use the
Safety and
Safe Value settings in the channel settings page for the throttle channel.
There's also a
wiki page
on creating a sticky throttle hold that works on the 7e, you'll just need to use a different switch in the last mixer instead of RUD DR0.
Do not ask me questions via PM. Ask in the forums, where I'll answer if I can.
My remotely piloted vehicle ("drone") is a yacht.