1. Let me declare an interest - I know the programmer who wrote it - Simon Salter of Chersoft. If you get the Nautical Institute rag- "Seaways" you will find a brilliant article by him in this month's edition on the mathematics of chart projections for electronic charts.
2. It is considered by professionals to be an excellent programme - the UKHO have sold, and are selling, a lot of copies and I have not heard a single complaint.