With CS5.5 on OSX, after saving a file and reopening it, certain frames (and their artwork) end up missing, i.e. aren't saved with the rest of the file. This happens with random frames. Other artwork, created after these frames, is still there. Anyone else run into this problem?
In the Flash Help menu, please click on Updates. The Flash CS5.5 updater fixes some issues similar to what you're describing. Once you're done updating the version number in the About Box should show 18.104.22.1689.
Flash Pro, QE