Object reference not set to an instant of an object.

Hi Guys, I am relatively new to grasshopper but i have used it a bit, for some reason every time i try to open one of the definitions a friend gives me I get a warning message (attached). We both have the same versions of rhino, and grasshopper (Newest ones, Rhino 4 SR9) and the same plug ins installed, we already tried reinstalling every single component of the software and found no solution, please, we are going crazy if someone knows how to fix it, or has an idea, please share.

My Friend has a MBP, dont know if it helps.

Thank you.