AVG claims that TBB contains malware

I installed the Tor Browser Bundle about a week ago & it extracted fine, worked great.  Accidentally deleted it earlier today (& emptied my trash before I realised Tor'd gone in there).  Just went to download the Browser Bundle (v 1.3.23) again & it again downloaded & extracted fine.

But when I went to start browsing, my AVG (v 10.0.1209) insisted that it contained malware - rated 4/4 in threat severity.  So I let AVG take care of it, but it freaked me out a little.  I'm hoping I just managed to muck something up at my end, but I don't know how to tell.

I'm not a programmer & feel way undereducated on things like this.  Is anyone able to advise whether this was a genuine threat?  Or if it's probably not a real threat, why would AVG "detect" malware at this start-up but none of the other times I started Tor?

I'd really appreciate any thoughts.

Trac:
Username: munster