As a long time fan of the book this is apparently 'based on', I was somewhat sceptical. However, I have enjoyed film adaptations of most of the books I am fond of, so I wasn't expecting to completely waste my time.
The best thing that can be said for this film is that, looks wise, Dakota Blue Richards is relatively close to the description of Maria Merryweather. The script is appalling, the casting fairly inappropriate, the acting from Natascha McElhone in particular is horrific (and straight out of a provincial pantomime as the Moon Godess). Even the CGI is unimpressive.
Obviously, personally I would have been best pleased if they had stuck to the actual story, but failing that, the re-write they produced could have been done well. Instead, within half an hour I was wondering about the cast and crews' sanity, and within three-quarters of an hour, my own.
In saying that, the music is incidentally pleasent, and the setting isn't bad. Moonacre Manor has an exterior that is relatively close to the description in the book, as is the castle of the de Noir clan - although both have been enlarged. Maria's 'Moon Godess' boudoir is pretty, and will probably set any little girl to dreaming for a bedroom like that! (But then, so would the description in the book.)
The worst thing is, having bought the DVD, I don't even want to pass it on to my younger relations, as even they, at the ages of 8 and 12, will find this film beneath them. Buy this for little girls under 6 if you must; they are likely to enjoy it a great deal - but better to spend the time reading the book to them - and it can be appreciated by all ages.