OK, thanks for the info..
Kind of an odball thing to do but maybe there was some reaon, As I run in a double nat setup I setup rules to open multiple machines via the internal router with one rule covering multiple ports and then added a secondary rule at the secondary internal router. Then today discovered I could not edit the rule to add one extra machine with a new port without re-entering everyting, or else setting up a totally new rule for the one machine. Seems a somewhat odd restriction!