David:
Same thing happened to me with my first few attempts with Sketchup and Maxwell - my rendering was completely washed out with light. The best thing to do is start simple.
I assume you're using '3ds2mxs' for exporting from Sketchup. At first, I would encourage you to use ALL diffuse materials, no textures. You also must play with the camera settings - start with an ISO of 100 then try a few different shutter speeds and f-stops. That's the key to keeping your rendering from looking completely washed out. After you've got the rendering to look pretty well lit, then go back and start experimenting with textures and glass and emitters. Also, read the few threads about Maxwell on Sketchup's forums.
More info would help as well.
Hope this helps.