Yes, you can install Rosetta in Snow Leopard. It is a customary feature on install, and even if you don’t do it then, it will ask you the first time you start a power-pc programm. If you click yes, it will just download Rosetta from Apple’s servers.
thanks for the quick answer! But no, it gives the same message as before: “file format not supported or file damaged.” All clips are shown as offline. I suspect I have the same problem I read about in another thread: the 4.1 update shot my mpeg-codec, so I guess I have to reinstall…. ah, premiere!