Did you use RotoBrush or old-school masking to do your rotoscoping? If it’s RotoBrush then ensure that you Freeze completed frames – hmmm, freeze-d frames or otherwise, RotoBrush data is contained within the AEP – similarly for masking.
There’s a strong likelihood that something else is amiss. It could be your system, it could be the one at school.
Try sending the existing AEP to a friend to see if they have a similar issue. Look at other avenues to troubleshoot and if still failing, come back with more details.
Cheers
RoRK
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