I thought the Celtics struggled much more with the new officiating changes than the Raptors did, and it threw off their flow. For example, the quick two foul calls Horford got when he tried to roll after setting a pick, and rolled into a incoming defender. That was not an offensive foul in the past, its a new wrinkle in how the NBA is calling stuff this season.
Also the 14 second shot clock reset after an offensive rebound instead of 24 seconds hurt us a few times, as did the increased emphasis on hand-checking on offense. Guys where just doing what they are used to always doing, and getting called for fouls all over the place. They will adjust to the new rule interpretations, it will just take some time.