Avid Support Codes

[Jmo9]

I was wondering if anyone has experience buying an Avid Support Code.
I have an issue that this forum was unable to resolve (http://duc.avid.com/showthread.php?t=339030).

I've never contacted a technician before. Here are my questions:

-With my PT 10 and Mbox, is it the Pro Tools HD support (at $79+) or The Pro Tools Software LE, M-powered, stand alone ($39+) that I need to purchase?

-Is there a refund if they fail to solve the problem? (forgive me if that sounds naive)

-Any other tips/advice in dealing with the techs?

-Anyone have positive or negative experience buying/using a Support Code?

Thanks.