FileBot

It seems like if I have an nfo with an imdb tt number and rename the movie with the help of IMDB it takes the nfo and extracts the imdb link. But if I choose TheMovieDB it doesnt use the tt link from imdb to determine the movie name? I think other software does this? I might be wrong anyway would be great!

EDIT found it here:
http://api.themoviedb.org/2.1/methods/Movie.getImages
http://api.themoviedb.org/2.1/Movie.get ... /tt0137523

Movie mode always looks up tt<id> found in NFO files. Why do you think its not doing that? The movie found via nfo should be one of the suggestions filebot will gives you (along other options determined in other ways).

Ok might be that the movie didnt exist in theMovieDB, guess it worked ok

Yep, imdbID lookup uses the selected data source. Might very well be that it's not in TMDB, and thus be ignored as invalid imdbID.