This is why I always choose the full installation, rather than the default "typical" most programs offer, when I install these programs. MS Word and WordPerfect both offer very good conversion in these cases.
All I do is to open the WordPerfect file into Word--and vice versa--and the conversion takes place. Sometimes I have to make some minor corrections in the format, but otherwise I have found it trouble-free.
As mentioned previously in another answer, it does not work as well to use the "Save As" feature in either program. I have found that this more often results in formatting errors.