I am on Esprit 6 current build using PNGs. I see it also using uncompressed AVI.  I can correct the problem somewhat by removing all the noise bumps from the terrain. But then it doesn't look as detailed. Presently just trying to find a compromise between settings/render speed/final output. tks everyone....

I am usiing some of the existing mats like Shasta rock and desert...You should be able to recreate fairly easy.  What you get will be the "crawl" of the mat as each image tries to calculate the bump along with camera movement.....

Windows 10 - Poser Pro 2012 - 64Bit - 24GB RAM - 4 x 3.40 GHZ processor