macOS/OS X Numbers 3.2 inserting date / time I want a cell to take on the date and time of "this moment", and then leave it.

Contrary to some experiences I've read about, the Insert menu does have Date &amp; Time, but it doesn't seem to respect the format I've specified for the cell.  I used the Cell formatting inspector to declare the cell as Date &amp; Time, 1/5/14, 7:08 PM. I entered text-insertion mode on the cell, and selected Insert > Date &amp; Time.  It inserted Friday, July 4, 2014 (and no time). When I then selected the cell (you know, one click, which outlines the cell, as opposed to two clicks which puts you into text insertion mode), the inspector said the cell's format had reverted to Automatic. I switched it back to Date &amp; Time but now it reads 7/4/14 12:00 (it's really more like 1:50).

The whole thing is anti-intuitive and zany to me. Can someone tell me what's the right way to command Numbers to insert the current date and time into a cell, and then leave it?  (=NOW continues to update)

UPDATE 1

The three methods I've tried for entering the current date and time into a cell are:


Enter text-insertion mode in a cell, Insert > Date &amp; Time (which enters just the Date, as Friday, July 4, 2014), enter cell-selection mode on the cell, and change the format to Date &amp; Time (which changes it to Friday, July 4, 2014 12:00 AM).  So, not that one.
Enter text-insertion mode in a cell, type =NOW (which enters 7/4/14 1:31 PM and changes all other instances of cells with =NOW to 7/4/14 1:31 PM !!).  So, definitely not that one.
Enter text-insertion mode in a cell, type 7/4/14 1:34 pm which gets changed to 7/4/14 1:34 PM (i.e. 'pm' got capitalized), indicating that Numbers did recognize it as a date/time.  This works. But it's less than satisfactory, to put it mildly.


I can't imagine this is working as Apple intended.
I believe Insert > Date &amp; Time (and its two companions) are intended for use in headers and footers. These are available after choosing File > Print. When used there, the inserted date can be clicked for a little popup formatter and button to manually reset the time to now.

The feature you want, an auto-generated NOW cell that does not change, is apparently not available. 

Option A: Put the NOW function into a cell somewhere.  It shows the current time. Copy the cell, then Edit > Paste Formula Results into the cell you want to have the unchanging time.

Option B: Use a general macro app (like the amazingly capable Keyboard Maestro) to generate your date/time text and paste it into a cell.

In both cases, choose the date and time formats you want on the final cell.

(Numbers 3.5.3 used for this answer)