If you generate frames one at time (i.e. 3d rendering) -- you might have missing frames in your sequences used in After Effects. Beware because CS6 makes this a massive headache. If someone knows a workaround besides a huge time-waster that is creating dummy filler frames, please let me know. Please submit a bug report to Adobe because this missing frames warning is a massive frustration... Feel free to copy/paste from below.
******BUG******
Concise problem statement:
The missing frames warning indicator IS HORRIBLE. It is intrusive, unnecessary and inefficient.
Steps to reproduce bug:
1. I Have loaded a series of sequential frames. They are coming from a 3d renderer so sometimes frames are missing and are filling in gradually.
2. Add the sequential frames to a composition
3. Scrub the playhead in the composition.
Results: Each time I touch the scrub bar, I get a warning "After Effects warning: The sequence has 335 missing frames." Next time I touch the scrub bar "The sequence has 334 missing frames"
Expected results: Pre CS6 -- The missing frames warning used to come up ONCE when reloading or loading footage... NOT EVERY time I touched the scrub bar. It is SO annoying. Make it work the way it used to in CS5. This current implementation is absolutely horrendous. It is completely useless and a huge waste of time for people who generate individual frames (i.e. 3d animators -- many of whom use After Effects)