Hmm... Bug 174992 reports the same error message as you are getting, but no one over there manages to trace it to the user trying to apply the effect to a non-path object... See what I mean about this extension being a mess! :)
Hmm... Bug 174992 reports the same error message as you are getting, but no one over there manages to trace it to the user trying to apply the effect to a non-path object... See what I mean about this extension being a mess! :)