Unable to export Landscape heightmap.

I read the documentation about heightmaps, but it’s completely different from what I see in my editor, so I can’t export the heightmap correctly.The items in the Landscape Export tab are extremely limited and almost impossible to operate. I can’t choose the resolution, the base height, or even whether to output the whole map or just a portion.
Also, it seems necessary to specify some file. When I selected the image, something was exported, but the contents were just a blurry white image.

The engine version is 5.6.1. The documentation seems to be compatible with 5.6, but have there been any major changes? Or is it just my landscape that’s broken?

anyone?

It looks like this part of the documentation haven’t been updated since 5.3 so there are probably some things that has been changed.

I can’t choose the resolution, the base height, or even whether to output the whole map or just a portion.

I looked at the documentation, and I cant find any resolution or height data for exporting, only for when you are importing.

However, if you use “edit layers”, you should be able to chose what part of the heightmap to export.

So does this mean that heightmap export doesn’t work currently?
I set a few things on import, but the only white image I was able to export just generate intense needle-like bumps. Nothing works anymore.