Nick Frosts character shaves his whole chest in one scene, but chest hair is seen to be poking out of his shirt several times through the rest of the film.
The end-credits magazine clipping "Sales Employee Of The Month" says that Helen Morgan has been selected since she met all the criteria "with flying colors". Since the film is set in England, that should be "colours".
During the end credits there is a flyer for a Latin Cruise which misspells Dance Lessons as "Dance Lessions."
Obvious dance double for Nick Frost during most of the non-close-ups and acrobatics.