I am having this problem too. I have read all these threads, tried the solutions with MP3 Rage and FileTyper, but still to no avail. Why would LimeWire change the resource fork anyways? If anybody has any solution to the .sit files not opening, it'd be GREATLY appreciated. To the LW dev team: I think your product is awesome but it seems this problem is a major headache for all, please take note and come out with a Patch or update.
Thanks