It took all of us a long time of reading and playing to figure them all out. Once you understand, it will be like a whole new world. Here are some resources.

http://docs.chaosgroup.com/display/VRAY2SKETCHUP/V-Ray+2.0+for+SketchUp+Help

http://www.youtube.com 😉

I already solution it … i made scenes and make a different archive for it… i erase what docent see on the scene… i had 180 mb and i reduce to 70 at each scene… know i have a problem rendering with distributed render….jaja thank you very much…aaa also cleanup help me a lot! thanks for your time

That was my experience, I was checking parsing time, and it ended up being about identical with layer off versus geometry deleted. There may be issues if there are extra materials that are in that off layer, it may be that processing materials could slow things down too.
Found the thread. Man, I wish they would fix the old links!
http://www.chaosgroup.com/forums/vbulletin/showthread.php?62797-Lights-and-Render-Time
Maybe I'll bump this for Fernando, I am very curious to get an answer from someone who knows...

Rojy....i try with the visopt...and it didnt work...it didnt make the render...i think this problem is strange....thankyou for the vispot and your time...