How to start a standalone map?

[BulStudios]

So i know the basics like saving your map, making companies/cities e.t.c as i've already made a fully working map but it was only a promods addon and now i've wanted to make a brand new standalone map but i can't seem to find a way to

- Select which country my map is in [i want to set a map in Bulgaria but i can't seem to find a way to make the car license plates to be Bulgarian and buying a garage crashes the game obviously because the game doesn't know in which country you currently are]

-Change the map scale so for example when the GPS shows 10km you actually have to drive real life 10km to reach your destination instead of the usual 19km ingame = 1km irl

-Change the map background so i have a 1:1 map of Bulgaria as background or atleast remove the default ets2 background so you don't see a map of Europe

That's it for now, hope anyone with experience can help!