Plot hole: When Freddy takes over Jesse's body at the party, there are several people watching through the patio doors when he confronts Lisa. None of these people ever make a sound, even when they see Lisa have a knife fight with a horribly disfigured man with long knives coming out of his fingers. The other party goers are completely oblivious to Freddy's presence until he comes jumping through the glass doors.
Plot hole: If the curse counts an eclipse as night, then Navarre should have turned into a wolf during the eclipse. If the curse does not count the eclipse as night, then Isabeau should have remained a hawk. In neither case would they both have been human at the same time.
Suggested correction: That is the whole point; it is neither day nor is it night. Each only suffers the curse when it is specifically day or specifically night. Any time it is not one of those two events, the curse is not active, as shown earlier in the movie when both are human for seconds during a time in between day and night.