How to convert .sco to .sli ?

I have made a street as an object ,
although it can be used in OMSI editor ,
but how can i convert the road (.sco) to spline (.sli) ?

I don't really understand how to use the OMSI Street Creator ,
when i click on compile street , it requiers a .txt file,
where can i get the .txt file ?

Thanks for your help !

Ok, the main problem is of course, that we haven't released an English SDK for building splines...

You cannot convert .sco to .sli. Sli files are just text files which describes a profile which will be extruded. The street converter tool is just some kind of easy way generating sli files from easier text files... but we will describe this in detail in our SDKs...