Ah, I''m using version 11. The file -> open doesn''t work for me either. There is a reasonably good document at the maxsea web site that explains how to work with S57
charts:
http://www.maxseainc.com/assetts/MaxSeaS57.PDF
There is a new release coming out shortly, I''m told. Hopefully they continue the usability improvement trend. Maxsea is good functionally, but is not exactly intuitive to use.