Well,
You have the answer right in front of you.
Search this text in the error dialog box & read very slowly "SQL server has gone away" (because, I agree, it cryptic).
This means that the communication between your web server and your SQL server died.
This is might be a hosting problem, a far too complicated SQL statement (very long treatment, which is not the case here), and normally it indicated that your SQL is overloaded, the connection times out.
On a shared server, your not the ONLY user – there can be many more.
One thing for sure: this has nothing to do with the Armory Addon.
PS : Instead of hitting PrintScreen for every question and paste the entire image on the net, why not starting paint, do a Paste and select the important part of it.
This make the image smaller and more clear, doesn't blow up this forum layout, speed the transfert time (discharges the web server of WowRoster, which makes its SQL connexions more stable
), making having you having an answer faster ^^