That all sounds like simple wiring issues. Most probobly bad earths or bad contacts.
Lights need positive and negative to work.
Buy a cheap test light from super cheap auto and trace backwards from the lights in question (Including the light fixtures etc) testing for power on the positive untill you find the reason why there is no power. trace the negative wire to check it earths properly.
An afternoon, about 8 beers and methodical patient work should see all your problems fixed.
You may need some spade connectors, small length of wire, wire cutters and a crimping tool.
this is for an American 66 but it should be close
http://www.1966vwbeetle.com/1966%20Wiring%20Diagram.htm
