Hi, I am glad that you liked the game. It is unfortunate that your e-mail was not delivered. That is probably result of spam fighting. I should create some more reliable alternative contact or multiple ways to contact me.
ad 1) As the game is small and it is not connected to any public translation web then only valid option is to send an email with the translation.
ad 2) There are not many control keys. Just SPACE bar to pause the game. I should better add keys configuration in the game settings.
ad 3) That is interesting. Not sure how to correctly support such scenario. The game also supports light and dark theme so such thin would need to be supported in both modes. I will think about that. Perhaps metro lines can be also represented by various types of lines.
ad 4) Yes. In general I would like to have support for various platforms. But that is not easy as that depends mainly on used compiler and libraries. Used Lazarus/FPC partially supports Android but it is not easy task to extend the game for that platform. It would be better with Delphi IDE which supports Android but that is commercial product with limited Community edition. So that is on my TODO list but not planned in near future.