XYZ file terrain modeling

Hi SketchUp Community!

Is there anyone who can summarize the steps from an ASCII-File into a terrain model in SU?

My aim is to import an ASCII-File with more than 135.000 points. While searching a lot I came up with two possible ways.

First is to import a *.dem-File. This one crashes every time I want to import, see all this comments. Contrary to SketchUp 2018 ArcMap import the file without any problems. Second one is to convert the ascii-File to the Collada-Format *.dae for example with MeshLab or Blender. Therefore I did not make any result yet.

I prefer any hints in order to import XYZ from ASCII into SketchUp.

Thanks a lot!!
Simon