Those were ravens not crows.
The pentagram is upside-down for "black magic", it should have been inverted. Pentagrams are protective.
Crows aren't carrion birds. They are omnivorous, corpses are just an easy source of food.
When Jane sees the doorknocker he says goats are satanic. Not only is this nonsense, it's offensive nonsense.
Firstly, Wiccans don't believe in Satan, he's a Christian invention.
Secondly, Christians made up the goat connection to try and make the Horned God a symbol of evil. (Around the time they rewrote half their "facts" about Jesus to steal Yule and the spring festivals.)
A blood ritual requires blood, Tamzin was very obviously using milk.
When the agents first go see Tamzin Dove, all the cars are driving on the left side of the road instead of the right, and the steering wheel is on the wrong side of the vehicle, thus the film was printed backwards.
Jane uses a single paper clip to pick the lock. Lock picking requires two tools, one to jiggle the tumblers and the second, stiffer tool, to turn the barrel.
The witch is represented completely wrong. There is too much to list but for one a witch is not a high priestess of Wicca. Second a Wiccan, which she means to call herself not witch, does not cast spells that cause harm. Third, they don't even believe in magic in the way Hollywood makes it seem. They believe in energy and have the power to control this energy. Wicca is a religion just like any other.