Driving R/C boats and cars well is one thing, flying a plane in 3 dimensions is another. Your skills will help you but take it slowly and shoot for a lot of straight and level flying, clockwise and counter-clockwise, after you get it up a "few mistakes" high.

I can't help you specifically with the Merlin because I've never owned one but I'm sure someone knowledgable will chime in and help you out. Have you checked Megatech's website for a downloadable manual for the Merlin?