I am running Premiere on an iMac with 2gb Ram.
The project will only render about 200 frames of about 5000 frames in the project. The project is only about 5 minutes long. When I open the project some of the clips say 'Media Offline' but if you drag them slightly in the timeline viewing window they appear. None of the transitions work until you move them slightly and then they appear. When you close the program and reopen the clips are back to media offline and the transitions are gone again.
When I exported the film to a .mov file the transitions still didn't work despite the whole project rendering, supposedly!
The green render line only appears on top of a few clips and the ones where the transitions don't work there is just a blank space - no red line.