A snapshot will just plot the time of sale again. Which is why you are seeing a double print. This is not seperate transaction but the same one. I a similar problem when trying to view time of sale on excel through Reuters because all it does it takes a 1.0
sec snapshot.
Time of sale seems to be a lacking element in many data and platform vendors. Tradestation offered great time of sale but I do not have it anymore. I am looking into esignal data and charting to see if their TAS can be modified to filter out big lots like Tradestation.