Your settings in "Security & Privacy" may be preventing MindCastr from installing properly. Go to System Preferences > Security & Privacy > Tick Anywhere. Make sure that you unlock the lock symbol on the bottom left of the window. Simply click it to unlock it.
You may have downloaded MindCastr too many times, if you have more than one copy of MindCastr on your computer, it can often cause issues. If this is the case, DELETE every single file/folder of MindCastr and Download/Install it only once.
The third possible issue might be that you don't have JAVA, you need JAVA to run MindCastr, download it for free here: https://java.com/en/download/index.jsp
If you are still not able to run MindCastr click the button below.