OSX Mountain Lion doesn't start on PD7

MBP2010 with Mountain Lion
PD7 last updated, can't start Mountain Lion on Virtual Machine after first reboot on installation. Just gray screen with apple and nothing ever. (With Lion on VM ok!)

Anybody can help?

 

Same problem - Mountain Lion won't run as guest in Parallels 7 on Lion

Parallels 7 August 3 2012
Macbook Air Late 2010, 4GB memory
Lion 10.7.4

- Created Lion guest using recovery partition and installed all software updates
- Opened App Store and downloaded Mountain Lion
- After overnight installation process, guest screen shows only the Apple logo on grey background
- prl_vm_app is taking 99% of cpu (out of possible 200%)
- restarting virtual machine leads to same result

 

There is an update

On a chat session with support, they provide me with the link for the updated build for Parallels Desktop 7. There is a related article in the KB: http://kb.parallels.com/114449 It says you go and download the last version in the provided link.

 

Different problem

The problem isn't that Parallels won't start on Mountain Lion. The problem is that the Mountain Lion virtual machine won't start in Parallels running under Lion.

My version of Parallels is Build 7.0.15106.

 

I downloaded the last update and I am able to open a previously created VM with Windows 7 as guest OS.

The About window on Parallels says: Build 7.0.15107 (Revisión 796624; Mon, 03 Sep 2012).

 

Unfortunately, I have the same problem with .5107 as well.