The base has a flat section - it's actually an ice cube holder.
When I bought it (before I opened the box) I thought I may drill lots of minute holes in it and then rig it up with a small torch bulb inside so it lit up the holes (modellers, eh?).
But when I opened it I saw that it was made from rubber, so that was no longer an option since I would have to find some way of making it rigid (hence filling it with expanding foam).
I did think of painting small yellow dots, but I canned the idea since I'd have to do shit loads to get the idea across and I thought that 1/ I'd get very fed up with doing so many and the standard would therefore slip and...2/I doubted I could do them small and sharp enough.
So I did a Google image search to see if there was a way of painting it so it wasn't just a slab of grey. I saw other models that some had done and they'd done some panels in a different, browner shade. But when I looked a pictures of the actual cinematic model it was...just grey.
So I decided I'd leave it just grey. And I thought I'd rationalise that at that viewing scale/range any lights would be so small that you wouldn't be able to see them. On a bigger model (this one is about 12cm diameter) then you may be able to see lights, but this one is too small for that.