So, for all you roof-watchers, this is the post you've been waiting for. Ta dah!
It's not quite finished, obviously.
However, here is a snap of the roof skin glued in place with the cut out for the domed end very prominent.
What I'll do next is cut some sloping triangles to fix in the gap.
These will act as a base for the Milliput and also reduce the amount of putty that is required which will also keep down the weight of the roof.
One of the risks with this technique is that the carriage could become a little top-heavy - especially so in this case because there will be virtually no interior because it has been all stripped out for the dancing!