No regulations prohibit the carry in casinos. As private property, they're obviously allowed to ask you to leave.
The law states you may be in possession of a firearm so long as your BAC is less than 0.10. The DUI limit is 0.08, so if you're OK to drive, you're OK to be in possession of a firearm. If you do happen to find yourself in a situation where you're BAC exceeds 0.10, the law does say that permanent confiscation of said firearm is only justified if the person is irresponsible, such as improperly handling the firearm, brandishing, etc.
Some folks say Northern Nevada casinos are more willing to accept carry by patrons, in fact one person even mentioned he was carrying for several hours while sitting at a blackjack table playing cards. I am always concealed here in Southern Nevada when inside a casino, because I hear the exact opposite is true. And I don't feel like the hassle of finding out.
Open or concealed in your car is OK with or without a permit. Carrying OC-style on your belt holster is completely legal while driving. It can also be in your dashboard, center console, trunk, under your seat, in your glovebox, whatever. Without a permit, just don't conceal it upon your person (in your pocket for example).
Have fun and good luck. Tell your buddy THANKS FOR THE SACRIFICE from the rest of us.