See
this page for nitty-gritty details of the red, green, and yellow render bars and rendering preview files.
> I just got the book, An Editor's Guide To Premiere Pro, and it looks like it will be a great jump start.
That is a terrific book. Read it through carefully and watch all of the videos on the DVD.
(Full disclosure: I'm biased. I'm the book's technical editor.)
Here are some other good resources for getting started with Premiere Pro.
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Todd Kopriva, Adobe Systems Incorporated
Technical Support for professional video software
After Effects Help & Support
Premiere Pro Help & Support
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