i think ive got it. So i connect the two neutrals together in a connector block then the live that comes from the fused spur to the common terminal and the live that comes from the wire that leads to the lights in the L1 terminal. Also its RCD protected.
The markings are common, L1 and L2. The dimmer is brand new and i have got the lights working but not the switch live as i can only turn it off by the fused spur.
I have wired a new dimmer switch that is feeding two wall lights.
I have spured off a normal socket which is then wired into a 5amp fused spur and then onto the dimmer and then onto the wall lights. I think i have done everything correctly apart from the wiring into the back of the dimmer...