this is what imean always at asgvis whe you are using vray. imho, if you are trying to use all these artificial lights (without sunglight)... do not use the camera yet. it will greatly confused use without really knowing how vray works.
you see in vray sun, is very bright, so you need to use your camera in order to balance the harsh lighting.
like what stinkie said, why not visit the main vray site. there are even basic tutorials there.
that black there is because of the camera). in order to correct it. 1. read the manual 2. if you are lazy to read the manual, then you either increase your light multiplier for your omni or rect lights or you have to adjust the camera exposure...