The sunroof paste is pretty expensive but it is special (from reading here.. my sunroof cable is bust so I don't know). You can ask the dealer to get it for you.
The switch could be pried off the dashboard. It's pretty easy. Gently use a screwdriven on top of the switch and pry it out of the wood plate.
Be careful not to chip the already brittle wood..
2008 BMW 335i Coupe