You are confusing UWB with HF route a bit.
Anyway, i made the mistake of trying to watch this movie with people who didnt read the VN first. Regardless, i didnt like it (wasnt even able to finish it since then..). The animation is great, the fights are cool, but no story, no characters, no dialogues, no motivations, no anything that made the VN so fantastic.
So i came to the conclusion: the right way to watch this movie is to sit down to your computer, start the VN, get to the 3rd day, go for the UBW route and whenever there is an action scene, press alt-tab, and watch that 4-5 mins of the movie, then pause it again, alt-tab back to the VN, and keep reading (dont skip the scene, coz many times i acutally liked the descriptions a lot more than the movie itself).
(i will try to watch it till the end when i get the chance, but really, even tho i remember more than enough of the VN to be able to follow the story line, it is just annoying.)
Something must be wrong with me. I'm giving advices to someone i should kill.