This is the standard exterior lighting setup. When you create a Vray Sun, it automatically adds a Dome light with a Sky texture.
Solution: This usually means the texture path is broken. Vray 2.0 does not auto-archive textures. Go to Asset Editor -> File Path Editor -> Remap lost textures manually. Vray 2.0 For Sketchup 2015 64 Bit
For those
Without proper light, a render is flat. Vray 2.0 offers specific tools optimized for SketchUp 2015. This is the standard exterior lighting setup