So far I have not found a way. I just added an extra track and platform... If that is not an option, you might need to look for a different mod ;-)

Either you add track crossings or a subway. Then, connect your crossing or subway entrance to the road. You can help yourself with ultra thin paths from my mod "street fine tuning".

Now, you can add stairs as well and connect them to my new pedestrian paths or bridges, and then to the road network.

Originally posted by lollus:

Now, you can add stairs as well and connect them to my new pedestrian paths or bridges, and then to the road network.

Awesome, thanks so much!

Cross reference, see https://steamcommunity.com/workshop/filedetails/discussion/2363493916/3189116454986197714/

We really need a short piece of platform-height path that can be placed at the end of a platform as a middle-piece between the platform and the stairs asset.

There is an asset made like a piece of platform, it is in the same section as the stairs, check it out. You can also:
1) use a piece of platform-track
2) use one of the platform exits

I get no lanes connecting to the platform end. I tried with the cargo platform, the stairs' mouseover info claims it works with cargo.
I want to have a narrow cargo island platform for postal service only, no heavy goods.

An island platform for cargo? Uhm. Have you tried the track crossings then? Otherwise, send me a screenshot.

The first thing that's needed on all occasions of an island platform is something to connect to the narrow end of a platform with connecting lanes, no matter if pax or cargo.

I don't see the track crossing parts on a cargo station anymore.

I play with
https://steamcommunity.com/sharedfiles/filedetails/?id=2617346426
and tried to find some issues with yearFrom but the track crossing modules say
so they should be available.

Island platforms work well with passengers, I have never used them with cargo coz I have never seen one in my life. They haven't got a narrow end because they are rectangular.
If you want to give track crossings a try, download this: https://github.com/lolluslollus/lollo_freestyle_train_station_1
and let me know.

They help a lot. Thank you.

I am glad. By the way, I think I know what you mean: you want entrances and exits axial to the platforms, right? I might actually add those, I will see if I find a cheap way of adding them.

Exactly. At the end of the island platform to add the stairs or elevator asset between the tracks and build an overpass.

I have bodged up something, download it from https://github.com/lolluslollus/lollo_freestyle_train_station_1
and see if it works well.