I have tested this a bit and haven't found bugs, although my test have not been that meticulous
I think this is quite innovative tool, haven't seen one like this done before..
I myself don't have use for templates but I think many people would have...
All I can complain about is that the drop down menus don't have all the stuff you will have when right-clicking on some window, like the 'group window' and that there are no exit/cancel buttons in some of the editing windows that pop up during the course a creating the template, like the 'group manager' window for example..
In addition to those save/load features you already mentioned..