The default Gatekeeper security setting in System Preferences > Security & Privacy blocks the installation of non-conforming applications.
If you attempt to open an application that is not from the Mac App Store or from an “identified developer,” you’ll be stopped with the error message
Here is a simple message to allow RapidStudio software to run on your MAC
At the top of the Mac screen click on the "APPLE" logo
Click on the "System preferences", once in there, click on "Security and privacy"
Then in "Security and privacy" ,under the "GENERAL" tab right at the bottom you will see Allow applications downloaded from:
You need to select "ANYWHERE"
and that's It you'll be able to use the RapidStudio software!