I had a project that was edited in 2.0. When I open it up in CS3, all of the title clips and animated gifs are shown on the program monitor as offline (red media offline screen). In the Bin, the titles and gifs are shown online. I went through each clip: Reveal in Project; Replace with Clip from Bin. I was able to correct the 50 or so "Media Offline" clips. When I save the project and then reopen it, the titles and gifs are gone again. If I import the project with the missing clips to another project, the clips are OK. But then, when I close that new project and reopen it, the clips are "offline" again.
This project was originally shot in HD (Sony FX-1) but the finished video is just on a regular DVD. The project settings I selected were DV-NTSC Widescreen 48Hz. The mpeg video clips are always there but not the titles that were created in 2.0 nor the animated gifs.
Then I added an animated gif in CS3. It too goes "Media Offline" when the project is reopened. Again, the titles and gifs are shown online in the Bin and can be reloaded to the Timeline but go away when the project is reopened.
I have another project that was shot in standard definition video and edited in 2.0. I selected DV-NTSC Standard 48Hz. It works fine in CS3. But, as I mentioned, the HD video clips are not missing, it's the titles and gifs that are missing.
Windows XP Pro; 1 GB RAM; 400 GB Hard drive (two 200 GB RAID0)