This script should be compatible with versions of JAWS going back at least to version 4.x. Just paste the entire thing at the bottom of your default script file and then in the body of the script hit the key combination of control+D. At that point a dialog box will open up that you can tab around and fill in the appropriate items for example the hot key you wish to assign and so forth. I normally use control+shift+W. I find that control+shift key strokes rarely interfere with other key strokes at all. N. B. this is not an exercise that a beginner should take on if they are not comfortable doing it. Once it's installed then just hit the key combination you've assigned to it and JAWS will either say maximized, restored, or couldn't find the symbol. That last is what it will say on the desktop because there are no symbols for JAWS to read in the upper right hand corner of the screen. There are other places it will say that, but the desk top is a good example.
Script SpeakWindowStatus ()
If GetWord () == "Restore Symbol" Then
Say ("Maximized", OT_STATUS)
ElIf GetWord () == "Maximize Symbol" Then
Say ("Restored", OT_STATUS)
Say ("Couldn't find the symbol", OT_MESSAGE)