can anyone advise how to operate reversers on touchdown? F2 doesnt activate them..

Do you use a throttle for thrust, or the keyboard? I'll assume you have a throttle, since I had this problem with my last one. The reason I had that problem was that the throttle was old, and the potmeters worn, so when I would press and hold F2 to start reverse thrust, FS would keep getting spikes from my throttle, cancelling the reverse. The solution to my problem: Buying a new throttle!

Or press F1 then hold F2. If the throttle isn't at minimum the reverse thrust won't work.if your keyboard has a f lock key make sure it's on!