Replacing Dimmer Switch

Hi,
I'm looking for a bit of advice on replacing an old dimmer switch but I'm a bit unsure of the wiring on it.
Its a double one way dimmer switch.
One knob is for the main lighting and the other is for 2 small lights on the wall.
One knob is physically broken, keeps turning but the other knob functions.
This is what the original wiring looks like, there is some kind of a looping wire.




I connected a new standard switch (Non Dimmer) and wired it like below.
I connected the red wires to Com (Live) and the grey to L1.



Only the main lights came on with this configuration and I later discovered that 2 lights in 2 different rooms no longer worked.

I've rewired the old switch back up and the problem with the 2 lights in the other rooms has been resolved and the good knob works as previously.

Anyone know how I should wire the new switch, do I need to loop the red wires as previously ?
Many thanks