I'd first check to make sure that you're running WordPerfect 12, which is the current supported version. I believe it is the same version in both ES and ES2.
After that, you might want to look in the Cafe tool (http://adobe.com/go/cafe) and do a search on "generator Wordperfect" and found the TechNote at http://kb2.adobe.com/cps/402/kb402754.html
Other than that, I'd suggest a call to support.
BTW, Cafe rocks and is a great place to start looking for solutions.