We went to MCT for Christmas.Great place.When you arrive at LHR go to the F wing at the south end of T5.Check in,go through security into the F lounge,and exit and go to the CCR.Bag storage on your left and reprobates at the bar diagonally to your right.
On arrival at MCT you need to queue at the money change to buy your visa,then straight out through immigration.If you like a good curry Mumtaz mahal is excellent.
The flight home is now a morning flight,and security was not very busy when we left.
BA have a second security check for them,and that is where laptops etc must come out.
I hope you have a great trip.