I'm using Adobe Flash CS3, working on a project with dozens of symbols, and the editor is running very slowly. Would it be more efficient to export the symbols and import them through code, or is there another way to speed things up?
Exporting your symbols would be a good idea. Assuming an empty FLA doesn't slow you down, you could expect the same speed performance.
That said, a compiled FLA with library assets creates for a larger swf. Everything (usually) must load before you see anything, whereas as dynamically loaded assets are more responsive, as it offloads the wait time to after StageReady
.
Two other ways to speed things up: