Remis Roof light

I have jammed the Remis roof light on our Broadway EB in the closed position, and can't lift the dome so as to try and dismantle the lifting mechanism, and hopefully get it to work again!

I have looked online at u tube and other sites, and there were a couple of videos showing possible remedies, they however had open roofs and I don't.

Does anyone know how to take the dome off, so that I can try attempt a repair.

Thank You

(Replying too late to help you I expect, but...) 

Have you managed to take the inner cowling off? That gives you access to the fixing for the outer housing to the inner ceiling (in similar way that a sink is attached to a worktop). I can't see how to take the dome off from the outside, all fixing are from inside to outside on my Vario. Maybe removing the whole of the outer cowl+dome+assembly is possible without cutting free the outer from its sealant base? would undoubtably make off-MH investigation easier as you say.

I had fo have the lifting mechanism replaced they weak and are prone breaking

The blind/flyscreen housing is simply levered off the ceiling. It is held by a number of strong spring clips that fit over 8 (?) ball shaped studs mounted to the inner frame/ceiling and projecting down from the ceiling. Insert a strong pallette knife between the ceiling and the frame an inch or two from any corner and use it as a lever. The clips are quite tough but will, with care, release from the balls. That may enable you to see what has jammed the lifting action.  My remis is simply hinged at the front with a turning catch to secure it closed or slightly open. I don't recall anything that could allow it to jam.

I have a problem  opening  mine because the roof light sticks to the seal after a few weeks of being closed , I break the seal by running a credit card between the light and rubber seal  to break the  bond ,and push the light up with one hand  while rotating  handle  . Could be worth a go