You may see any of the following dialogs when trying to open a MapTool app (for the first time after downloading) or the DMG.



You can continue with the install using the following method.
Click on System Preferences in the doc (or Apple Menu -> System Preferences)
Select Security and Privacy In the General Tab change the "Allow apps downloaded from:" to Anywhere Now you will be able to reopen the DMG and install the App, once you have done this remember to set the "Allow apps downloaded from" back to either of the other settings.
Once you have installed the app you will not need to do this every time you rerun it.
As we would not be able to get an Apple developer ID for RPTools due to Apples policies, this is unlikely to change any time soon
