Tom,
 
  To add a key is the easy enough...  
 
  You go into the tas 5 compiler and go to maintain dictionary under the Database menu.  select the file you want to add the Key to then when it comes up on the screen press Ctrl-K then  select Add a new Key.  
 
  Now once you save and exit you need to restructure the database. Again in the Database menu go to maintain dictionary but instead of entering a file press Ctrl-O then select Restucture. and enter the filename there.
 
 That's it...
 
  Now making any programs use that index is up to you and will Orphan those programs from being updated by anyone else but you.
 
  Good Luck