I worked on Buccaneer Flight Systems at what was then HSA Brough from 1970 until the aircraft went out of service in the early 90's. You are to be congratulated on building an outstanding flying model of an aircraft which had some pretty challenging flying characteristics in its full sized form.
The powerful trim changes arising from flap and aileron droop, particularly with BLC on, were well known from early flight testing. One of the early development batch aircraft was fitted with extended chord ailerons and was lost near Holme on Spalding Moor when the nose down pitch produced by a full droop selection could not be overcome. The extended chord ailerons were abandoned after that.
A decision was made, I am not sure by whom, to instruct the pilot to select flap and droop in small stages rather than complicate the system by having an automatic interlock if one surface failed to move when selected. I think the navigator was supposed to look over the pilots shoulder and monitor the indicators in what was a pretty high workload stage of flight, particularly if it was a carrier approach. After many years and several accidents in service, the company was tasked with introducing a comparator which would stop all the surfaces moving before the pitch change was uncontrollable if one failed to operate. This was quite challenging as the position sensors were Desynns which were not easy to interact with. The mod had to be 'minimal change' as the aircraft was by now quite long in the tooth. We were still working on the system and the final report and testing of a working mod was produced several months after the Buccaneer went out of service.