Install is damaged and can’t open
I know that there’s nothing wrong with the software installer, so I poked around the MBA 13’s System Preferences. When I checked under Security and Privacy, I realized how the Mac OS, Mountain Lion, handles unwanted or unsigned apps.
The default setting for Mountain Lion is to prevent unsigned apps from running. The solution is simple change the settings under Security and Privacy, so you can load 3rd party apps that did not originate from the Apple App Store.
The setting can be changed by going to Finder | Applications | System Preferences. Then select “Security and Privacy” and on the General Tab under “Allow applications downloaded from,” select the radio button “Anywhere.”
If you are worried about security, you can change it back to allow only from the App Store or identified developers after you’ve installed your software.