Microstation Connect Draping Issues

Hi Everyone

I wonder if anyone can shed any light on a problem I am experiencing using MicroStation Connect?  I have a really large terrain model that I want to use for a visualization.  I have surfaces which I am stitching together as a mesh.  Generally I work in AECOSIM BD, but as the meshes are so large I am trying to use MicroStation Connect - it seems to handle the meshes better.  The problem is that our system is not set up for Connect yet, and I am struggling with the materials.  Usually our drape is set by Part and Family.  In this instance, I have assigned the dcdrape material from the old palette to the  material.  I can see (by turning the drape on and off in the raster dialog) that it is working as the raster file disappears and the terrain changes color, but it becomes a solid green rather than an image.  Not sure what is causing this, I wondered if I need a different drape palette?

Also, once I have finished with the terrain model I will need to export it to LumenRT. The ribbon in MicroStation Connect does not have an option for Large Model Export - any idea where to find this?

Any advice would be gratefully received