Boost gage on 2016 Z06
 

Boost gage on new Z06 reads -13 on start-up. Manual says it is supposed to set to zero (center position) on start-up. Is this a problem or, perhaps, means a leak in Supercharger PSI boost?

Not having a 2016 Z06, I can only guess at what you are seeing. It may be that the gauge is reading vacuum as well as boost. That's what my gauge on my C5 Z06 does.