I just installed 8.08 on my new Win 8.1 computer yesterday, and got the same hit on tmgss.exe as described in the original post. AVG automatically removed the file from the "The Master Genealogist v8viewer" folder. I don't see anything in this thread about how to avoid this problem, so FYI here's what I did.
First, I copied the tmgss.exe file from my TMG 8.04 installation on my outgoing computer into my 8.08 installation on the new computer.
Second, I changed some AVG settings. AVG has a way to exclude items from scans, but says in the article that the exclusion only applies to "potential" threats, but not not "viral files". The procedure is described in question 7 on http://www.avgthreat...n/content/faq/. Instead of excluding the specific file, I excluded the whole "c:program files (x86)The Master Genealogist v8" folder. Then I ran a scan on "c:program files (x86)". No threats were detected, so it looks like I should be okay.
Third, another precaution I took was to uncheck "Heal / remove virus infections without asking me" for future scans. That way if tmgss.exe is identified as a threat again, I should be given the opportunity to retain the file.
I guess I'm taking a risk by excluding the entire TMG installation from the AVG scan, so I hope Wholly Genes keeps its install bundles clean.
I'd be interested to hear any other solutions or experiences.