I was able to find a way to do this using a trick. I had another VM that was PRO (no MCE key added).. i went to HKLM\software\microsoft\windows NT\CurrentVersion Exported that whole key and to HKLM\Software\Wow6432Node\Microsoft\Windows NT\Current Version and exported this key. I'm not sure which parts of these key(s) were the "key" but i suspect the ProductNAME, ID and DIgitalProductID.. So I imported this on a vm that was PRO+MCE.. I then immediately ran the Windows 8 Retail Setup, using the PRO key and it did an in place upgrade. Afterwards, thus far, everything looks correct.
Well, I sorted that out. Wow6432Node isn't needed.... the problem is in CORE only. We can't downgrade to CORE
Firstly, are using that RC key in RTM?? That is funny Secondly, ProWMC & Pro are separate edition & thus require separate keys to be activated.
Noop.. the tool can't do it solely. After using this tool you need the installation media too for doing the downgrade. Btw there is some problem in x64 editions, I will fix that asap.
Need to downgrade from Pro Media to Pro! Any hint when 1.2 will be released? I'm having similar problem. Have Dreamspark key for Pro, used key that was supposed to be a free upgrade for Media Center and it deactivated my registration. Tried running 1.1 but after rebooting and trying to use media to install with original key I only get option to install saving files (thus all programs would be wiped). Need to just get rid of Media Center!