We posted a new build of the free version today. This solves one problem of crashes when rendering when the render window is closed and the SketchUp window is maximized on larger high resolution screens.
A second change is an update to the Material Preview Window. If you have a multicore PC, we use a second core (and other available cores) to perform the Preview.
Unfortunately you do need to go through the same page to download it again. Sorry about that. http://www.idx-design.com/IDX/IDXRenditioner/FreeVersionofIDXRenditionerExpress/tabid/1011/Default.aspx
Thanks for your feedback and patience.
This is an out of date post, the free version has been discontinued and is no longer available.