It was relatively hard to get back to where I was ... there are no obvious menu selections to restart this. I actually closed and restarted Flash to make the option visible again.
Actually, I had left the tutorial open while doing other thing. But, of course, Flash (yes, the error box said it was Flash) crashed IE and all the open pages closed. The only other program that normally crashes IE is Acrobat ... hum, another Adobe product.
Adobe Video Workshop
Getting Started with ActionScript 3.0 in Adobe Flash CS3 Read this before starting ... it is VERY good. 5 pages as of 02-08-08 ... and still being written. Many sections are still marked as TODO.
However, be careful of the other tutorials on this site, for instance, the tutorial on how to add MovieClips to the timeline via code applys to ActionScript 2, in ActionScript 3 addChild() performs that function.
Unfortunately, this site wants you to load the MOST recent version of Flash (188.8.131.52) before it lets you see movies recorded in Flash 8 - completely ridiculous. Solution - download the flv files and view them with a local viewer. The newer tutorials require Quicktime.
Also, some of the examples use ActionScript 2 code that is not available in ActionScript 3.