Yeah I'm up for that Andrew, Between us we should find something new I'm sure,...just poke me a few days before. I'm pretty local should be able to meet you.
I have a lot of urban star trails that I did with an Uncle as a lad in the late eighties, he owned a factory under the spaghetti junction of Birmingham's motorway network and we spent hours, well I mostly copied him, shooting some pretty impressive combinations (wish I could show you but I don't have a scanner...shots are a little lacking in lustre, old and faded anyway IYKWIM)
One of the tools he often referred to was making up cardboard cut outs to block overly bright areas. ...Have you tried this way? (sorry I've read your dome blog but not the urban)... Its probably the solution to the Docklands excess light problem...like that shot above, If we had one vertical rectangular black card (to match the building..Oh and a bit for the train) held in front of the lens, that could do the trick?
just about timings after that...