I did: https://www.waze.com/forum/viewtopic.ph ... 01#p815801
I borrowed and modified Dave's code to my liking – of course anyone is free to do whatever they like.
On the default scheme, the railroads are largely the same as Dave's, except I like to have the labels on them; my runways are much thicker and I kept the yellow color just for fun (there aren't that many runways out there and they don't usually conflict with roads). I used the default scheme's code in Randy Mac (my custom theme) as well.
On the night scheme, the railroads are still largely the same, albeit with labels, and much darker to match with the scheme in general. I made them grey where most roads are blue, to allow easy differentiation between roads and railroads. Runways are thick like in the default mod but grey for nighttime.
I also added light toothpaste-green city polygons to the default scheme.