Hello jvwjgames, Sorry you are having this issue.
No, it should not, but there no harm in saving the map file some where else for a backup. If you have your own custom media, or media you have converted from past model packs. They should be fine.
Note: If you changed any of the stock models, textures, file setting, I would back those up, as those will be over written by an update.
I would try shutting down Steam and restarting first then trying again, before uninstalling it.
Reason. GameGuru is sending packets to steam in intervals, Mayabe one of there servers was unreachable the moment you press the start GameGuru button. It happens all the time, Internet is not a perfect system and is actually down more then you would think.
So maybe try that first.
The back up of your media is important and should be backed up anyway just for your own sanity.
Let me know if this helps. I will check back.
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