DATA VALIDATION WITH AUTODATE

CAN SOMEONE HELP ME TO PREPARE A WORKSHEET WHEREIN ;;;
1. DATA VALIDATION BY LIST OR CUSTOMS IN F2:F1000
2. AUTO ENTRY OF DATE n NAME WILL BE FILLED IN G2:G1000 - TO SHOW DATE
[NOW() OF ENCODING and THE ENCODER NAME.
3. UPON SAVE/CLOSE = F:G with encoded data and date will be freezed or
locked. SO that when the file will be opened again, any other encoder cannot
commit a mistake to change the previous encoding. i HOPE THIS IS POSSIBLE AND
NOT VOLATILE....thanks
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"Bright minds are blessed to those who share them.."-rsb.