Hi. I'm glad you're finding the program useful.
Are you importing the landscape into FlowScape? that program has a feature where if you try to import a mesh that is too large then it gets scaled down. Exporting a landscape at 8x zoom seems to be triggering that feature.
the larger version was exported at 4x zoom while the smaller one was exported at 8x
If it's a different program that you're having the issue with then let me know and I'll look into it.