I've seen this movie yesterday, also during the Film by the Sea festival in Vlissingen.
I really liked how the movie started, lots of tension building up and the special effects are very well done. If you want to learn more about the 1953 flood though, then this movie might not be the best choice. I was hoping for a more in depth movie about this subject, but the movie focuses more on a personal story that happens during (and partly because of) the flood.
The overall acting was mediocre, and only Sylvia Hoeks as our main character seems to be displaying some genuine emotions. The first thing I noticed was that the actors use almost no local dialect ('Zeeuws'). Even though it's not very realistic and probably done to appeal for a larger (Dutch) audience, I liked the choice.