Unity 5: Monodevelop not loading

I recently downloaded unity five, none of my old stuff worked anymore so I just started again, however when I try to create and open a script monodevelop pops up and then instantly Dissapears. About 20 seconds afterwards the script opens in another completely unrelated coding program called Xamarin studio. In which It does not recognise any unity code (For example: transform), When I try and enter the code, it does not pop up with the usual suggestions.
I would like to find a way of fixing this which does not involve deleting all of my unity files. I am running on A mid 2007 iMac using OSX Mavericks.

Most likely, Monodevelop isn’t linked to unity at all. It’s just an .exe fie so its not a case of Unity being broken, its just an app not opening. Try installing Visual Studio Code, that runs much better on OS X