I've decided to make the whole trainshed roof as a single piece with a flat sheet underside for strength and for the rectangular skylights and curved central section to sit on. It will make the construction somewhat more straightforward and less fraught.
Having been trying to find detailed on-line pics of the trainshed roof (from above) they unfortunately seem incredibly rare - although there are plenty of the underside of it from the platforms. Those I have, and have seen, seem to indicate that the 'clear' sections on both the rectangular skylights and barrel vaulted central section, that do let a little light through, aren't exactly clean and glass like and hardly look like windows. They appear to be corrugated and just a dirty brown section of the structure they are part of.
Because of that, and that I've also not found any suitable N gauge scale clear corrugated embossed styrene, I'm making the whole roof solid with the 'clear' sections simply painted as an appropriate dirt colour. Besides it was always dark in the terminus part of the station. However, the model will get a little light in from above the side walls (as with the real one), due to the roof being raised a little by truss support beams, although seeing inside will still be difficult.
