WordPerfect does not keep track of margins for an entire document, only for each paragraph. In ClarisWorks, individual paragraph margins cannot be outside of the margins set for the whole document. For example, consider a WordPerfect document in which all paragraphs but one have a left margin of one inch. The fifth paragraph out of ten has a left margin of zero. When this document is brought into ClarisWorks, the "global" document left margin must be zero, even though there is only one paragraph with this margin. Since there is always a possibility of encountering a paragraph with a zero margin within a Word Perfect document, and since in ClarisWorks, individual paragraphs must have margins equal to or greater than the "global" document margin, the WordPerfect filter sets the value of the "global" document left and right margins to zero.
Currently there is no workaround to the issue.