We have a nice structural warehouse with all its beams, column and trusses. The model is pristine when Navigating no problems at all, but when we render; objects dissappear. Parts of the model become invisible in presenter mode. Some column dissappear, parts of trusses dissapear. Very strange stuff.
Attached is a pic mid-render. It has been print screened and cropped so it doesn't look sharp, but is shows how parts of the models are missing.
The backround is an image of a crane on site. This Image should show a nice rectangle building with gable roof style trusses.