From my ceiling rose I have:

2 reds (loops)
2 blacks (neutrals)
2 green/yellow (earths)
1 red with black tape (switch)

They attach to a connector block for new light with the new light LIVE going to the switch wire in the connector block. The has the light working fine.

However, the two nearby bedroom lights do not work.

Do I have to insert a piece of link wire from the switch wire to the two loops wires to send power to the bedrooms?

Swebster67, October 2013

you don't link the switch wire back in to the loop.Have a look at this http://www.ceilingrosewiring.co.uk/ceiling-rose-wiring-new-cable-colours/

Sparks, October 2013