It's not that bad an option actually. There is a bit of walking from probably something like gate K95, used by that Nostrum flight, down to the middle of the main T4 building for the transit to T4S. There are moving walkways that take you most of the way, but only on the apron side of the building, not the inner channel. You can actually use both lounges, Dalí is nearly en route for the transit, but I wouldn't bother, just go to T4S. You have plenty of time, and the Velázquez is one of the better European lounges. I would market the positives here, you get to leave MAH at a sensible time, none of this silly dawn dashing around, and have a reasonable connection at MAD, couple of hours in the lounge, and still get to London not too late in the evening. MAH is a pleasant and small airport, but there is no lounge there. I wouldn't turn up much before 12:30 hrs.