To start a new project after you’ve been editing another one, choose File → New Project. Or close all windows and then click Create a New Project in the Create Project dialog box (Section 184.108.40.206).
Figure 4-14. Top: An iMovie 6 project is a single document icon on your hard drive if it began life inside iMovie HD. If it began life in a pre-HD version of iMovie, it was, and still is, a project folder.Bottom: If you open one of those project folders, you find a long list of files. Don’t move or rename any of them. It’s worth knowing, though, which ones to open. For example, the iMovie document icon with the shortest name is the actual, live, current iMovie HD project—the only one you should open.
Here’s another new feature in iMovie 6: You can have several projects open at once. Just double-click them in the Finder, or use iMovie’s File → Open command (or File → Open Recent, whose submenu lists the last few movies you’ve worked on).
The advantage of keeping multiple projects open is, of course, that you can copy and paste clips between them. The copy/paste routine goes exactly as described in Section 5.7.3, except that after copying clips from one project, you can switch to another one (choose its name from the Window menu, for example) before pasting.
You can also drag clips from one iMovie window directly into another (using either the timeline or the Clips pane as the starting or ending points).
The fine print: You can’t have more than 10 windows open at once. The more windows you open, the slower things get. You can’t import video into more than one project at a time, or even edit another project while importing is going on. In short: Don’t get greedy.