depending on where your steam installation is, something like ...SteamLibrary\steamapps\workshop\content\ After that point it is unique to your pc, but if you search for '20181221' in that location you will find the zip file you need. Also make sure you have unreal 4.18 and visual studio 2017 as the compiler to get it working

UE4 habe ich installiert, 20181221 habe ich auch gefunden, jedoch enthält dieser Ordner keine Zip datei ?! Was soll ich tun?

I installed UE4, I also found 20181221, but this folder does not contain a zip file?! What should I do?

it may show up as a folder for you depending how your windows explorer is setup, but copy the contents to another location and open the file BusSimulator18.uproject that will launch the unreal engine. There is also a way to get it through the epic launcher, i cant remember quite how you do it,just that it is located somewhere in the library tab of the epic launcher

Danke für das schnelle Antworten, habe es jetzt geschafft, mit UE 4.18.3 anstatt UE 4.25 (auch die zip-Datei war da, jedoch habe ich nicht bemerkt, dass ich sie schon extrahiert habe. Meine Datei heisst nur BusSimulator18 und nicht BusSimulator2018.uproject)

Thanks for the quick reply, I have now done it with UE 4.18.3 instead of UE 4.25 (the zip file was there too, but I didn't notice that I had already extracted it. My file is only called BusSimulator18 and not BusSimulator2018.uproject)

good luck with it, can be hugely frustrating but also very rewarding when it all comes together and your driving your new map!