Just received the Dutch TV ratings for Season 1 from Eddy. Eddy's did a great job in collating all the figures.
Regarding the ratings dip for Episode 12, Eddy said "Ep. 12 has, in my opinion, less viewers because RTL4 (same company) had a movie at the same time,"
All data collected from: http://www.kijkonderzoek.nl/ (in Dutch)