Andre, sorry for my latelate reply - been troubleshooting this and many other issues.
With some stroke of luck I was able to migrate the Exchange Server off this host - didn't do anything fancy just tried to migrate it and it worked. Thought I was in luck and tried it on the Blackberry Server, totally forgot abot the SQL server on it and that freaked out big time. So I have had to rebuild that server and repopulate the users, they were not happy at all.
That now leaves me with this last server which is the firewall. Finding time to shut it down to try the steps you mention is proving quite hard and your last sentence gives me the chills "If the VM powers on without issues" IF oh man it's got to. 