Hi Roland,
Size can often be a problem yes.
The first part of my question is defiantly a place where size can be a problem, and the export of a dxf file, I have a understanding will become a huge problem even if trying one baseboard size.
What I did use the old program I lost sadly for was to get a piece of the land, for instance a area of 30 by 50 meter of a very mountainous piece where I needed to subdivide the ground into something Trainz can not give me, cuts and tunnels where I had a small mining set up with structures, holes, railroad cuts and so on in a tight spot, and the 5m grid was still to big to be useful for me.
Reading out the grid points into a text file would beat the job of doing it manually inside of Surveyor, no need to be a dxf file even if that is the simple way for me as a end user to use.
Of course, I have no idea how to accomplish anything of this as programming is way over my understanding of the world, I just mention the X, Y, Z info as a text info in case that was a easier way to just get the info out of a gnd file.
Thought since you was able to write such a file, you might be able to read it too.
Just Wish the Trainz Programmers had long time ago made such a utility them self, read the gnd file, send it to a xml or what ever and let people have a option to play with that and send it back to the same program to get it back into Trainz.
That way all you needed to do with TransDEM was to write to such a standard format, but, alas, so far Trainz seems stuck in not let people get scenery in/out of the program in a easy way.
Anyway, thanks for the discussion. I wish I still had the old program so I could have sent you a view if you had been interested, but alas.
I remember it created the simple mesh thing, that I saw in gmax was named plane I think, a simple one side flat square of two triangles per 10m grid.
Best wishes from still rainy Norway