Actually, in this case, the name doesn't have anything to do with the ZZ bird game. Rather, it means screw or spiral, and refers to the mechanical nature of the locking system. As OWD notes, there are similarities to the Scott spindle, but it's basically upside down, with the screw coming up from the bottom (which is why none is visible in the top lever).

Doverham, French doubles are very difficult to date accurately. V-C is indeed still in business, and they may be able to give you a range of dates within which your gun was produced. My best guess would be between the wars; less likely, perhaps shortly after WWII. But V-C no longer has most of its old records, and they won't be able to date the gun for you by serial number. However, when I wrote them years ago about a V-C gun I owned, they were kind enough to furnish pages from a period catalog which allowed me to identify the model, and to come up with a ballpark range of dates.