Steve - on my machine (running Xl2010) your wood spreadsheet did have the Lotus compatibility boxes checked. and the steel spreadsheet didn't.
When I deselected the boxes in the wood spreadsheet the range names went back to cell addresses, but if I re-applied the names they then stayed put.
In xl2010 it displays the Lotus compatibility for each sheet separately, and they were checked for the Wd-col sheet, but not the Data sheet.
Another difference from the behaviour you described is that, if the Lotus compatibility is selected, when you press F2 to edit a cell the range names change to addresses in the cell display, but stay as range names in the edit bar at the top of the sheet. If you don't change anything the range names remain when you press enter. If you enter edit mode by clicking on the cell the range names change to addresses, as you described.
So it looks like the problem is related to the Lotus compatibility setting, with an added bug in xl2007. I'd recommend an upgrade to 2010 anyway (if you can still get it), which has many other advantages over 2007.
I just checked in xl2013 (which I'm not so keen on), and it retains the range names in the edit bar both when you press F2, and double click, so if you are having this problem with a lot of files 2013 might be the way to go.
Doug Jenkins
Interactive Design Services