Sorry Dan, must have hit the enter kit by accident on my last response.
Any way, here is my suggestion:
In your form init method:
SELECT ;
MAX(id_field) ;
FROM table ;
INTO ARRAY aHighestID
IF _TALLY > 0
THISFORM.object.value = aHighestID[1] + 1
ELSE && No records on the table
THISFORM.object.value = 1
ENDIF
This should do it for you.
Good luck