Sorry I missed this one until now... I saw the film last week and really enjoyed it, and came up with a storyform for it last week, though not 100% sure on everything. But it has a lot of similarities to what you are discussing -- IC Issue of Preconception, Benchmarks of The Past & Memories, etc. I actually had the OS in Psychology though, although maybe that's wrong, but it made some pretty good quads at the element level (RS Problem of Disbelief and Solution of Faith! IC Problem of Uncontrolled and and Response of Help!) It did seem to me that the Overall Story problems were internal, however I might be mixing things up because of a sub-story (see below).
Belle is definitely Steadfast. And I didn't mind the Beast's change to let her go; true love means willingness to sacrifice and putting the people you love ahead of yourself (RS Issue of Morality?).
The rose petals are definitely just a clever way of showing they're running out of Options. I bet if you watched the film carefully, each petal dropping would symbolize a different option that failed. (And technically the last petal could have taken a year to drop, or three minutes, so it's definitely not a Timelock.)
I had the exact same thought! With the Beast in Situation it seems that everyone at the castle is basically in the same Situation, the same curse, and they all influence Belle in the same manner.
I was wondering though if there might be a sub-story about the Town and the townspeople that has an OS of Fixed Attitude. (It's even possible that Lefou is the Change character there!) And I felt some weirdness when the townspeople came to the castle at the end, sort of like the way they melded the two stories together was a bit rough / unexpected. Although by the very end the weirdness was gone -- it was only a small rough patch.
But that's why I find it hard to be certain of a storyform, because if there is a sub-story, you have to really be clear about what belongs where and what the scope of each story is.