Personally I would not have considered it feasible to have a light controlled by a dimmer and a rocker switch and I found some basic circuits here...
http://www.danlers.co.uk/dimmers/wddimmers.html
...which show how to do it. It seems however that you need three switches - two for turning on or off from either station and a third (the dimmer) to set the light level.
In your scenario I think you need to consider each light entirely separately. The dining area is a simple light + dimmer and it should be relatively easy to remove the single rocker for this and replace it with its own dimmer.
As for the lounge with two on/off stations (two switches) the diagrams show only one dimmer in circuit.
If you try to wire two dimmers to control the lounge light the only way i can think of is to arrange the dimmers in parallel - each feeding the light independently of the other.
So they are both off and you turn one on and wind it up to half.
Then you're at the other end of the room and all you can do with the other dimmer is make the lamp brighter - dimmer No1 is still feeding the lamp at half power. To turn the light fully off you need to go to both stations and turn off both dimmers.
Might be best to either; do away with the dimmer for the lounge and just have two on/off switches as before - or - do away with two control switches and have just one dimmer.
Quite what effect two dimmers feeding the same load and connected in parallel will have on the operation of the dimmers I'm not sure. Dimmer A on half will be terribly confused with full power being pushed into its output terminal from Dimmer B.
Let me know how you get on and remember Lord Finchley (look him up)
Good luck...
Peccavi
January 2009
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