I encountered a strange behaviour of Povray 3.6 when doing CSG with a mesh2
object where some parts of the object, reflection and shadow is missing.
Please have a look at
http://news.povray.org/povray.binaries.images/thread/%3Cweb.4110ab4b4cb2fb55602399d40%40news.povray.org%3E/
for an example image with detailed description.