SPC is looking for a eight-digit string, your devices ESN in Hexadecimal. Be sure to enter it with capital letters! Get your Hex-ESN in the settings tab -> Device Information.
And the file is located here, the exe and dll...
http://forum.ppcgeeks.com/showpost.p...&postcount=156
You put your hex-esn in the top box, then hit the button, and your msl is in the output. If you are still having troubles, pm me your hex-esn and I'll return your msl...