Vw 2011, renderworks not rendering

[jtml]

I have been trying to render a 65 k model in vectorworks 2011 on Mac OS 10.6.7, on a new 17 inch mac book pro 2.3 Ghz Intel core i7, 4 cores memory 8 GB, AMD Radeon HD 6750 and Intel HD Graphics 3000. 250 Gb free on hard drive (i hope this is enough technical info).

When it gets to the load phase the rendering just stopes. and when I do a batch rendering i get a black image. All quiet quickly (it stops rendering after about 3 mn)

I can render all the layers of the drawing separately. its only when i render the whole model in renderworks that it doesn?t work. Open GL works fine.

Is it only a question of my model being to big? (I get no message what so ever)

And if yes how do i know were the limit is. Sometimes i have had model were a reboot of the program would do. but not with this model.

This is very frustrating.

Cheers Jtml