Hi Volker, sorry for the delay in responding to this. Although this issue looks similar to others we are aware of that have to do with floating point accuracy, it appears that it has somewhat different characteristics. I have narrowed the source of the problem to your large-scale Contintent node in the Terrain group. It is very possible that it has something to do with the large scale or large *range* of scale being covered here, but it's hard to say for sure.
In any case I have logged this issue in our tracker and it will be looked at more closely as time allows.
- Oshyan
