@rad-we
i have some experience while using chameleon regarding SMsystemuuid, its better that you don't have this value on chameleon boot.plist or smbios.plist
why
while i put smuuid value in smbios it just generating new nvram-smuuid.plist, so we will get two nvram-smuuid.plist extra folder, the problem is when we delete the old one, then we will have new random MLB and ROM value every reboot, and you can't modify MLB and ROM value,
to fixed it, don't delete old nvram-smuuid.plist, just let it have two nvram-smuuid.plist or i suggesting you to delete SMsystemuuid value in smbios and/or chameleon boot.plist, because actually we don't need it on chameleon, we just need same MLB and ROM value if you once activated it
you can see at my value, it doesn't need random value or something like that, what we need is registered by apple server, the value could come from real mac, or by contacting apple care
and you can see both have different platformuuid but both have same MLB and ROM value and both can be used to activated iMessage