Hi Martina,
Great to hear youve been experimenting with method! The best way to find out the correct syntax with any field would always be to export the table (perhaps add a dummy record if the table is empty) and open this file up to see what Method expects.
That being said, the correct format for the CloseDate field is;
2015-Nov-12 10:00:00 AM
Thanks Martina!
Regards,
Ben