Hm, just got an idea what probably happened. Until today I had opened positions in both Z1fx & Z2fx. Today Z1fx closed the last position and it probably stopped updating the balance (equity) indicator. Then I restarted it, and it was in sync for the moment, but as soon as the Z2fx positions changed the equity, they desynchronized again, as the window with Z1fx didn't update anymore, and the window with Z2fx running did. I don't know if that's to be considered a bug.