Yeah, they're perma-flashy unfortunately. In fairness though, with ATS light cycle times, I think that's probably for the best.

I'm going to assume you've gotten as far as making your city definition(s) in //def/city/<city_name>.sii... Did you also remember to include your city via //def/city.<mod_name>.sii? That should look something like this: //def/city.some_mod.sii SiiNunit { @include "city/happy_town.sii" @inc...

I can probably be of some use creating the occasional map/sign assets.