Issues related to osg export and lightmapping

[Samuli]

Hello,
I'm exporting a lightmapped model from 3ds Max 2014 to vizard 5 using osg exporter. In the lightmaps there's a circular black area near origo, what could cause that? There are only pivot points and fbx link point helpers in the scene near/in the origo, not any objects (ie. sphere) that would cause the black circular area.
At the first time when I imported the lightmapped model to vizard, the resolution and color of the lightmaps were correct, but when I exported again the exactly same model as an osgb file, some lightmaps had a lower resolution and a different color.
Some faces of few planar objects are not shown in vizard, even though the normals are correct and the faces are visible in 3ds max viewport and renderings.