not sure if this will be of much help. I have used sketchup for CNC work and some of the plugins such as stl or dxf converters are good such as the one here
[url]
http://www.guitar-list.com/.../convert-sketchup-skp-files-dxf-or-stl
[/url]
but i also use mesh lab software. I only use this for smallish models and prototypes so I am not sure how well it will work for you but try it

(meshlab.sourceforge.net)

exporting from sketchup as a collada file and them messing about with it in meshlab, it does seem to work but needs experimenting with depending on what you are doing

Hi there
I was looking for a way to convert sketchup files into different formats and i came across. Most people probably know about this but i though i would post it here as it seems quite useful

(meshlab.sourceforge.net)

hi there
this is quite a useful 3d pdf tool, as long as you have microsoft word or power point. There is a free version of it that works pretty well

(www.righthemisphere.com)

i have come across some interesting bugs and have no idea why they are happening. Using this in sketchup 7, i can't seem to use some of the prebuilt components. when using hinges etc the component does not travel in the same orientation as the hinge slider etc.

Any ideas on where i might be going wrong?