Thanks Oshyan, Chris and all,
I'm testing the new suggested settings now. Thanks for all the info. Very helpful. I'm trying first, to mix a bit of all. Increasing the blur radius and reducing (but not eliminating) the enviroLight's effect on surfaces to .5. (also tuned the memory settings to be more reasonable. We have a lot of ram here, so I suppose it never crashed for that reason? Though even with the higher settings, it never went that high. Anyway, I'll let you know what happens. Also, I tried some frame blending, and that certainly helps... given there is so little motion in the scene, it may be the answer in the short term... but the scientist in me cant help but do some more tests. We have a farm here after all!