TERRAIN MODEL NOT VISIBLE WHEN PRINTING CROSS SECTION IN ORD

Hi all, 

we just started a new project with OpenRoads Designer. I've setup the DGNLIB that needs to be configure the Named Boundary process for creating Plan, Profle and Cross section drawing. That is going well. I have my border, drawing model and sheet model created in my DGN file at the right scale and the annotations are fine. The only problem is when i try to print a PDF file, in sheet model, the existing ground (reference - named boundary - terrain model) is not visible in the PDF. But it is in the drawing model, sheet model. I can snap to it in the drawing model. 

Any idea?

Thanks 

Gilles