I tried the Lagos map last night – most recent build for Mac OSX 10.14.6 on Steam.
It never expanded beyond the initial three stations – passenger numbers increased at these stations, as we would expect, but no new stations appeared. It ran for approximately an hour. Eventually I decided to try to kill it by removing all the lines, and the passengers just like would clear themselves. The game would not end.
I did take a video on my phone of the instance if that would be helpful.
Does it happen on any other maps? And, random question but I swear it’s relevant, do you have a peculiar audio setup, or were you switching between wireless headphones and speakers? Mini Metro ties some of its updates to the audio thread’s DSP clock, and if it stops mid-game if the operating system’s sample rate changes, sometimes things just … stop. The game is meant to fake a DSP clock when that happens but I might have missed something.
I just tested it out – I replicated it on the Guangzhou map, so it does not seem to be map confined.
Nothing going on with audio in either case – just default internal speakers, no headphones/other speakers/etc.