[haus]

If nobody knows / replies to you, the way I look for reg changes is to set the notifications to one state, export the registry using Resco Registry, then switch the notifications and export again (to a different filename). Then I transfer the .reg files to the desktop and do a comparison with pspad. You only need to export HKCU and HKLM (saves a lot of time), generally speaking.

Here's a sample mortscript I tried building to switch from normal to silent mode:

Choice( "Profile","Select Profile","Normal","Silent")
Case(1)
	# NORMAL MODE
    RegWriteString ("HKCU", "ControlPanel\Profiles\","ActiveProfile", "Normal")
    RegWriteString ("HKCU", "ControlPanel\Sounds\RingTone0\","Sound", "\Windows\Rings\Ring-Generic1.wma")
    RegWriteDword ("HKCU", "ControlPanel\SoundCategories\Ring\","InitVol", 2)
    RegWriteDword ("HKCU", "ControlPanel\Volume\","Ringer", 1717986918)
    RegWriteDword ("HKCU", "ControlPanel\Volume\","Volume", 2290649224)
    RegWriteDword ("HKCU", "ControlPanel\Notifications\ShellOverrides\","Mode", 0)

    exit
Case(2)
	# SILENT MODE
    RegWriteString ("HKCU", "ControlPanel\Profiles\","ActiveProfile", "Silent")
    RegWriteString ("HKCU", "ControlPanel\Sounds\RingTone0\","Sound", "*none*")
    RegWriteDword ("HKCU", "ControlPanel\SoundCategories\Ring\","InitVol", 0)
    RegWriteDword ("HKCU", "ControlPanel\Volume\","Ringer", 0)
    RegWriteDword ("HKCU", "ControlPanel\Volume\","Volume", 0)
    RegWriteDword ("HKCU", "ControlPanel\Notifications\ShellOverrides\","Mode", 2)

    exit
Case(0)
    exit
EndChoice
exit

Unfortunately it doesn't work because something about the TP volume applet undoes some of the changes moments after they are made. But it's a start. Once you figure out the registry changes, plug them in the script in place of mine and the mortscript should do what you want.