To add N/C pins, add a property to the part witht the key NC and the value(s) of the pins that are NC separated by coma and no spaces.

S-a	Open the Place Pass spreadsheet
S-c	Open the Components spreadsheet
S-d	Open The design window
S-e	Open the Route Pass spreadsheet
S-f	Open the Footprints spreadsheet
S-g	Open the Route Spacing spreadsheet
S-h	Open the Density Graph window (Layout Plus only)
S-i	Open the Statistics spreadsheet (Layout Plus only)
S-k	Open the Packages spreadsheets
S-l	Open the Color spreadsheet
S-m	Open the Error Markers spreadsheet
S-n	Open the Nets spreadsheet
S-o	Open the Obstacles spreadsheet
S-p	Open the Apertures spreadsheet
S-q	Open the Query window
S-r	Open the Drills spreadsheet
S-s	Open the Post Process spreadsheet
S-t	Open the Padstacks spreadsheet
S-u	Open the Route Layer spreadsheet
S-w	Open the Route Sweep spreadsheet
S-x	Open the Text spreadsheet
S-y	Open the Layers spreadsheet