Only two "empeg" keys in my registry.
the first is under:
HKEY_LOCAL_MACHINE\Software\empeg\empeg-car
the second is under
HKEY_CURRENT_USER\Software\empeg
But on my system (which did ask for a serial number originally when I first installed it) neither has anything of interest there now
[there are a couple of older keys/values there].
I uninstalled the 1.0 of Emplode when 2.0 Beta came out.
The only other keys to look are:
HKEY_LOCAL_MACHINE\Software\SonicBlue\emplode
and
HKEY_CURRENT_USER\Software\SonicBlue\emplode
But again nothing much of interest in there that looks like a serial number.
So, have a look in these 4 places in your PC's registry it might just contain the serial number somewhere on your system.