Great Rick!
However stamina is not always enough. Yesterday I sent one of my RH11 projects to Adobe for analysis. The verdict is back for a Windows 7 environment. This has no problems in their environment. Windows 8.1 environment is still pending.
Regarding your suggestions, they have already been tried and with the same result as the first one.
My company's IT department suspects a faulty Windows viewer or Windows 8.1 installation and have decided to reinstall my laptop. I'll get back with the end result 
Cheers,
Erik (at the wrong end of the stick in Copenhagen)
Back again and this time with a flawless installation. My brand new top-of-the-line Lenovo tablet was stripped and reinstalled. The culprit seems to have been the OS installation (Windows 8.1). Though no smoking gun was found!
Now everything works as it should. RH11 is up an running and all upgraded RH9 Projects are running.
Thanks to everyone for their advice on the rocky road to a solution 
Cheers,
Erik