I suppose I can try to recreate the issue, but it's a bit involved and I've found a workaround. But, the fact the workaround works might be a clue to what I'm doing wrong.
I had a List working great but in order to make the list filter and only show some of the data, I moved the full data into an array that became the ListCollection's "data". That's all working great, but when I navigate to my list (basically addChild the list I want and removeChild the stuff I don't)... the cells in my list don't appear. Not until I physically scroll the content (and then everything appears correctly).
So, my hack that seems to fix it:
I had already been using the .validate() but by adding the two scrollToPosition methods it magically works.
Any ideas what is going on? I realize more code would help but it's sort of a non-issue for me now, but I'm very curious what in the world I'm overlooking.