http://www.wargear.net/games/log/623026

Moves 274 and 275 show that I took Argentina from Peru and occupied it with 2 units.  This move took a very long time to complete; the site seemed stalled for about a minute. 

After the move finally registered, I tried to attack Brazil. A dialog box popped up that said I did not own the current territory.

When I refreshed the page, the map said I did not own Argentina, and I still had 3 units in Peru.

Moves 276 and 277 show that I now lost the attack against Argentina that I previously won.

I'm not saying that I would have won this game if not for this bug, but it's still a bug.