I seem to have a similar problem with HM2. After enrolling on 888, on which I don't play anymore, the HUD has crapped on Pokerstars. The HUD is resetting to 0 hands for most opponents during extended play on the same table. For instance, my HUD shows 60 hands, the HUD for other players that were on the same table during the same time, show anywhere between 0 en 30 hands, and not all the same neither. Some have 7 hands, others have 2 hands. Needless to say that the stats are useless. As was HM helpdesk.
I had HM2 installed on another computer as well, on which I had not installed 888, and there it is working well.
On another note: how could you combine the stats collected on two different computers (same account name)?