Hi,
To get around this, you can
1) Attempt to open the app. When it doesn't let you, click "cancel"
2) Open System Preferences
3) Go to the Security & Privacy section
4) Go to the "General" tab, if it is not already open
5) Near the bottom there should be a button to click to open the app. You might need to click the lock icon and enter your username and password first.
After this, you should be able to directly open the app like normal.
This is security that Apple introduced recently, and the only way to get around it is pay for a fairly expensive yearly developers license.
Thanks,