I'm not entirely sure what you're trying to do here and I don't have the image map you were working with, which makes it a bit harder to determine I think. But it's a very confusing and frankly elaborate network to produce what appears to be a fairly simple result.
From what I can see I don't think the problem is coming from any kind of a bug in Terragen, something's just not configured right. Some parts of your setup pretty much guarantee that no texture will show up on the sides of your displacement because you've got your Blend Shader inputs *Inverted*, meaning white is black, and thus the large white areas you've painted in your painted shaders on the side of your object are essentially black and that means no texture will be applied there. Some of the other Image Map Shaders are working entirely differently, through a Distribution Shader with altitude constrictions, which doesn't entirely seem necessary either. Were you trying multiple methods to achieve a particular result, or were these two approaches trying to accomplish different goals?
Honestly I think it may be best just to start over with the texturing. You do seem to be over complicating it I think. I might be able to give more specific advice or an example if I knew exactly what you were trying to achieve with your texture (seeing the original texture itself would help).
- Oshyan
