Hi, I'm having the same problem. I love this plug-in.
I've looked on the server for older versions.I even tried removing the NivoSlider JS file (i don't like the slider, but my theme uses the files for its dropdown menu, which i really like. There is no other version of jquery in their folder. And I've successfully used vSlider with this theme before, so i don't think the problem is in the theme files...
Can someone please look a the site and help me with what I might need to adjust to get the slider to work?
Many thanks in advance.
PS: I know the site validation generates errors, but those are mostly tag/browser incompat errors & the slider issue is unrelated. I'll take care of those errors later. I got the slider to work before with the same errors. Thanks!