strange collision behavior after export from Sketchup?

[fivel_lab]

Hi all,
I have a few models that I downloaded from Google's 3d warehouse. I followed the instructions in this WorldViz knowledge base article, but there were some export options in my version of SketchUp (8) that weren't covered in the KB article.

I have no problem getting them into my Vizard world. However, when there is a collision, I sometimes (more often than not) get an error along the lines of:

File "<string>", line 1
viz.VizIntersect([1,3.180823,1.982500,6.559749,-0.822035,0.000000,-0.569437,7,-1.#QNAN0,''])
^
SyntaxError: unexpected EOF while parsing


I am wondering if the mysterious export settings may be the reason for this error. Any ideas?

Thanks much!