The problem you are having is possibly a problem which we have already fixed and will be available in the next build update of CADWorx PIPE (around July 30). Although, it does not indicate an error reading the A file - it causes an un-handled exception. If you will report this problem to cadworx@coade.com by sending one of your A files, they will test it and then send you a new bi-directional which should fix the problem.