All the details are in my first message.
I opened a model that is on the local hard drive (not the CD), edited it some, then right-clicked... the Save option is unavailable, only Save As is available.
(edit)
I just noticed that :
- if I DRAG the model from the Library icon onto a "new" modeler window and edit it - Save IS NOT available
- if I use File Open and navigate to the model,open it, and then edit it - Save IS available
- if I double-click on the model icon in the library, it opens a modeler window, then I edit it - Save IS available
This seems like a bug in the library or something when using drag and drop.