I lived in Oxfordshire (Bicester) for a while and my time there helped inspire me to collect British locomotives. From there, it was a very short road to begin scratchbuilding Hogwarts when my kids became hooked on the books and films. I would love to return to the UK - and maybe that's also in part why I was compelled to model Goathland Station as Hogsmeade.
I'm working on some LED lighting in various building windows, and I've been adding stairs to the walkway up from the boathouse to the Great Hall courtyard. We have another show the last weekend in October and I'll be sure to take more photos and video uploads.
Primarily I used "Flickering Amber Battery Powered Triple LED Light for Paper Lanterns." They're quite small maybe 1.75" long.
I just cut off the hanging string and secured a couple of them inside each building with sticky-backed velcro. The flickering is subtle and looks like candle or lantern light. In the Station, it almost looks like people are moving around inside the buildings.
We had a show this weekend, but I didn't take the Harry Potter modules -just the Key Biscayne, Florida module. It was a nice change to be able to enjoy running trains instead of watching the layout like a nervous hen every minute.
That one is a discontinued Walthers Kit. I found it new in the box on eBay. It is very similar to the lighthouse and 2-story dwelling with dormer windows on Key Biscayne just south of Miami.