Shadows not exporting

[steve6]

Maybe someone here can solve this dilemma--I'm exporting from SU into KT, but the sun and shadows don't export (they are turned on in SU). When I do small test renders, everything is fine, but with a larger model, nothing.

I do have low RAM--could that be the problem? In KT, I go to Settings, Sun and Sky>Skip (sun already exists) to preserve the SU settings.

Thanks in advance!