Within the PPCGeeks_OEM.rar file is a folder, Tweak-Menu Sounds, where this is an option within within the Kitchen to revert back to the WM5 click and pop sounds. The registry settings are below:
REGEDIT4
[HKEY_LOCAL_MACHINE\Snd\Event]
".Scheme"="Curr0"
"EventMask"=dword:01F7ED
"EventCache"=dword:600
"Curr0"=multi_sz:"alarm2","", "alarm2","default","Empty","alarm2","infbeg","infe nd","infend","MenuPop","HWandSW","","MsgBox","infb eg","infend","infend","alarm2","","","voicbeep","R ecEnd"
I can only assume that if you change the "MenuPop" and "HWandSW" strings to whatever the names of your sound files are, this might work.
Give it a go......