Put the jar file on the desktop. Now open Applications/Utilities/Terminal and type the following commands, putting a new line after each one:
java -jar YOGBOX\ Installer.jar
(When you type the last command, you should be able to type java -jar YOG then press TAB and it will fill in the rest of the name for you. Since the jar file name has an embedded space you need a backslash just before the space in the file name).
Whatever error messages you get, cut and paste them back here
This is what popped up after i typed all that in :
Exception in thread "main" java.lang.UnsupportedClassVersionError: Bad version number in .class file
at java.lang.ClassLoader.defineClass1(Native Method)
at java.security.AccessController.doPrivileged(Native Method)
The jar file was created using a later version of Java than you have on your system. Either you need to bring your version of Java up to date, or you need to run Applications/Utilities/Java Preferences and ensure that the 32 and 64 bit versions of Java SE 6 are selected and are dragged to the top of the list.
I would like to , but as long as I was here I thought I would just write it since you already knew . But if you have any ideas could you please tell me ?
Sorry, I have no ideas. I think it needs someone who's familiar with Minecraft to suggest a solution. When you post your question, it might be a good idea to look in Applications/Utilities/Console to see if there are any error messages logged when you try to start Minecraft. Post these at the same time that you post your question.