can't seem to enter dates
I've tried quite a few formats but nothing seems to enter correctly. Please help!
Not sure exactly what you mean. Dates are entered in the three separate areas; Month, Day, Year. While there are drop-down lists for all those, the year list can be extremely long! I've found it quicker to simply type the info manually. However, for the month, you need to type the number of the month (01 through 12) instead of the first few letters of the name of the month. If you'll look at the pop-up/drop-down list for the months, you'll see that's how they chose to list them; "01-January". So you will always need to type the zero for the first nine months of the year. Actually, even the "Day" needs to be two digits, so the same method applies to the first nine days of the month; "02" instead of simply "2", for example.
If you are referring to the "V" in the date of your example, that is simply the method many 'scientists' seem to use for entering the month. So "V" is simply the Roman numeral V or 5 in our arabic numbers. In the Date entry of Notes for Nature, you'd need to include the zero, of course. I've heard this Roman numeral 'behavior' is mentioned in some of the Help areas. I only learned it by reading some of the other threads here. It's a good habit to search the current list of threads and see if your question may already have been answered, BTW. But it's also a good way to be alert for problems others have had! 😉