got this working using windows 7 home premium 64 bit (retail) using
OEM PDVDd 7 (medion computers)
PDVD 7 Deluxe upgrade download (only the U/G key is needed)
PDVD7 Ultra upgrade download (key doesnt work as its a Deluxe to Ultra key)

install OEM 7 version
restart computer- important
DO NOT perform Deluxe upgrade.
install Ultra upgrade(run as admnistrator)
restart computer- important
run PDVD
use Deluxe U/G key to activate



EDIT: Once Ultra is installed you can update to
CyberLink.4617a_TaRe38_DVD081201-07

Once updated to 4617a - a further update (suggested by pop up) CyberLink.5711_TaRe43_DVD090826-05 failed to install and left me with no PDVD installed - had to repeat the install process from scratch.


EDIT: got the ultra key to work

install OEM 7 version - I got pdvd 7.0.2414.0
restart computer- important
DO NOT perform Deluxe upgrade.
install Ultra upgrade(run as admnistrator) - pdvd Ultra 7.3.3319a.0
restart computer- important
run PDVD
use Ultra U/G key to activate

It still claims to be the deluxe version butt playing King Kong HD-DVD as I type


EDIT: after 4617a hd-dvd menu use is messed up so reverted to original install with no update patch. without update patch some titles wont play at all and others start but fail after a few minutes of play - so not the HD-DVD solution for win7.