Certain systems may prompt users about installing applications that aren't downloaded from the app store. No worries! Our software is trusted if it's downloaded from our website.
Open your Mac's System Preferences and then select Security & Privacy.
In that window, select the General tab. On the bottom half of the window, you will see "Allow apps downloaded from:" grayed out.
Click the lock icon on the bottom right to allow changes. You will have to put in your Mac Admin password to unlock this.
After it is unlocked, select the "Mac App Store and identified developers" radio button option.
You should now be able to install.