Never mind ...
I renamed the diagram later in the process. When I reopened what I thought was the right one (my renamed one) it only showed what I initially started with.
Finding the incompletely named file, and opening it, all my work was saved as desired.
So ... SSMS will save the rename of the file but post changes to the misnamed one that was started with? It appears so. My steps were:
- Create a new diagram.
- Add the initial tables
- Later on, discover the diagram could be better named, renamed it.
- Saved my work up to this point.
- Continued work and added a class of tables that discombobulated all my prior work :)
- Closed the diagram and reopened the renamed one, which only showed the initial tables
- Created the first post
- SSMS mysteriously crashed, restarted it
- Upon restarting the Diagrams folder was of course refreshed by default. I could now see the incorrectly named file.
- Opened the incorrectly named file, discovering to my pleasure all my work WAS saved prior to adding the class of tables that jacked it all up, LOL.
So until the folder is refreshed ONLY the renamed file shows. It's not necessarily the one holding all the work. The original misnamed file wasn't in the list of choices yet.
Is this really a problem with SSMS, though? I would think if I rename a file and no others are in the list, that the renamed file IS the one current work is being saved to.