Welcome to BVEStation.
Are you getting as far as at least trying to open it up in Terminal?
I have it working flawlessly on my mac pro. Search around on the official openbve forums (http://openbve.trainsimcentral.co.uk/), somebody posted a compiled version of the program as a .app file that can be executed like an .exe on a windows machine. To update the program, simply open up the .app file and replace openbve.exe with the newest version of the .exe and replace the all of the subfolders such as the "data" folder.By the way, once you open up the openBVE menu, be sure to uncheck the "show warning messages" and the "show error messages" checkboxes. For some reason mono doesn't like to cooperate with openBVE's error and warning messages function; simply not rendering the button to ignore the warnings and errors.