Error message when loading Grasshopper

Trying to load up grasshopper on my MacBook Pro computer but with Windows 7 Professional operating system through bootcamp.  Rhino 4 works fine (cannot seem to install Rhino 5 either).  Have installed Grasshooper (latest) but when I try to load it it comes back with the following message (jpg attached)

Can anybody shed a light on this.

Many thanks

William