We have 500+ FLAs that are essentially a sequence of PNGs loaded into the timeline, with a bit of AS3 code thrown in for the controller.
If we import the PNGs into a new, empty Flash CS3/4 document, add the document class and save the file, the resulting .fla is approx. 800Kb.
If we import the PNGs into a new, empty Flash CS5 document, add the doc class and save the file, the resulting .fla is 18Mb.
The resulting Published SWFs are within 1Kb of each other regardless of version, so it's clearly nothing to do with the content or the exporter.
Anyone know what's going on? This has just jumped our storage requirements through the roof.
Update: in case anyone asks, the total size of all PNG assets is about 2.5Mb. Clearly CS3/4 is using some kind of RLE compression on the PNGs, which is fine. But that doesn't account for the additional 16Mb. What the heck is CS5 throwing in there?