I suspect that the error message actually reads ‘Attempting to use AppleScript which is disabled’. You can enable the option ‘Use AppleScript in Actions’ in the general preferences dialog in Freeway.
As that post elaborates, you may need to tear down your existing effects and re-build them in order to get clear of the problem, but you will definitely not have any trouble using the latest version of Carousel with the latest version of Freeway.