After reading consulting several existing threads about problems with Flash and Firefox (and, after several tests, Konqueror and Opera), I decided to downgrade Flash. After replacing the library (as certain howto's instructed), flash doesn't seem to work: the websites where I used to have problems with Flash now have a "Download Macromedia Flash" prompt rather than a gray window.

How do I get the downgraded Flash to work? Am I on a wild goose chase?