Here are some guidelines to follow when editing data in a grid control.
Commands:
Ctrl-Y will add a new record
Ctrl-T will toggle the deletion mark(leftmost column)
Pressing the Down arrow when at the bottom of a grid will add a new record.
Some grids have columns that have an index number for each record. This index number must be incremented for each record. When you add a new record, do not forget to give an index number to this record. Index number cannot have duplicates.
The leftmost column often display a deletion mark(small black rectangle). This mark indicates a record marked for deletion. The marked records won't be displayed the next time you edit the table, but they will only be physically deleted when you launch a system table maintenance from the system menu.
Be careful with blank records, you should delete them before exiting by using the CTRL-T key to toggle the deletion mark. Leaving blank records in a grid control can have unpredictable results.