Thank you for your interest in Grand Designer.
You can have a look at my sketchfab page wherer you can find mainly planets but also a couple of partial terrains made with the software : https://sketchfab.com/ignishot
You can only import a existing heightmap, in longitude/latitude format, but you can't import other textures, everything is generated by the software.
The software is still in development, but I'm alone working on it and I'm developing another undisclosed tool in parallel, beside my main job. I'm currently working on a major update on Grand Designer that will be available 'when it's done', hopefuly soon. And yes, I'm not really the best on the communication side
There will be certainly sales at some point in the future, but I have no date for the moment.
Gil - Ignishot