Have you tried rendering a very simple scene (ie a box)? If that works then I would assume it would be something in your model. The next step would be to set override materials in Vray settings to see if its one of your textures that is causing the issue. If it still will not render then perhaps take a look if lighting is causing an issue.
It also will help to post some more information regarding version of sketchup and vray and computer specs etc.
Rob