Unable to load Grasshopper on Rhino Evaluation?

I just downloaded the Rhino trial from Mcneel (SR9) and the latest version of grasshopper from the link above (0.8.0013).

I'm running Windows 7 and when I install grasshopper it says installed successfully but when I type grasshopper in the command bar in Rhino I get an error (see images).

Any idea what went wrong and/or how I may fix it? I'm rather lost.

Thanks everyone.

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