I am but a mere marshal at Lydden. Since the circuit has been taken over by Pat Doran they are looking to promote a much more professional image - I have no idea whether they would allow RC racing to take place or not.
Best bet is to get in touch with the circuit - I think the circuit manager is Amy Doran (Pat's daughter). Lovely girl with some outstanding qualities as the picture below will testify.
That's me on the left in orange with Amy in the middle of the Men and Motors girls by the way