Hi Pete,

Your right that the settings from the buddy Box Box transmitter should be in the range of the master transmitter and it seems that your values almost match. You may adjust these value on your buddy box transmitter by using the subtrim an the throw values of the gas channel to get exactly the same as for your master.
Do not forget that your master also uses the trim and you have to consider to set the buddies throttle low value to the master low value+trim set to highest value, otherwise your engine will stop running when switching. Small value differences do not matter, eventually your engine will run a little bit higher or slower on buddy box mode, but this is no issue.

Just try everything on the ground; I use the buddy box with a Graupner MC24 and a Jeti DC16 with no problems.