If she has difficulties with the movie environment, it is best not to start with 1st run movies, since one you establish a pattern of anxiety, it is hard to work backwards. The best way to start with movies is some second run or classic movies which your child is already familiar with on DVD. Do not plan to stay the whole movie just build up a little at a time (and do not go with the anticipation of seeing the movie yourself since in the beginning you need to be focused on her needs and status).
As for behaviors getting more pronounced this typically comes from two areas, first the world's sensory expectation get more complex and challenging as children get older so the limitations and accommodations must be ramped up to match to limit the "abuse" and associated anxiety based behaviors that come with it, second is that a large percentage of the kids who are install diagnosed as SID have additional differences in social skills and EF and she is at an age where expectations (both yours and the worlds) naturally increase in these areas, so when challenges and anxiety are from multiple sources, manifestations (initially behaviors) ramp up.
Please do not chase the behaviors, find the source, otherwise when will just keep moving from manifestations to manifestations eventually ending up with serious co morbid conditions like PTSD, OCD, ODD, chronic anxiety and so forth.
Fully understand your child's and her neurology and make sure you have competent clinicians (which are quite rare) accommodate for her sensitivities and needs and teach her the skills that she needs to adapt to the NT world to the greatest extent possible.
The movie "event" is a good example of what happens if the above is not standard practice, We all are learning, so move forward and as you accomplish the above suggestions you will find thing improve greatly.
bookwormde
As for behavios getting more pronouced this typcially comes from to areas, first the world sensory expectation get more comples as children get older so the limitations and