Nothing can take you out of a film faster than a changed ending that feels artificial. There were wonderful parts of this, mostly the striking cinematography (that carnival ride!!) and Richard Attenborough's performance. But the film's problems with pacing made it an uneven and disappointing effort.
To me, the Catholicism in the film feels muddled and confused, sprinkled throughout and then shoved in viewers' faces in the final act; from what I've read about the novel, it is more complex and masterful exploration of theology. Instead of a more layered psychological depiction, the film frustratingly treads a conventional path covered by many other noir and crime films. It's a shame, because the source adaptation had the potential to become a true standout of its genre. I truly want to see what the raving reviewers see in this, but unfortunately I think a lot of what they extrapolate about its achievements comes from the novel, not from the film itself.