WinDVD 8 Platinum Probelm w/Vista RTM x64

Is anyone else experiencing the following problem with WinDVD 8 Platinum in
Vista RTM x64?

I could not activate WinDVD 8 Platinum (which I purchased online) from Vista
RTM x64 until I ran it as administrator. At least that's what I thought until
the product suddenly quit after 14 days (the trial period). I would not get
any messages at all when attempting to run it.

I removed it and re-installed and at this point, WinDBD 8 Platinum confirmed
that the trial period has expired but I cannot activate it although I have a
valid license.

I have contacted InterVideo about the problem and beyond the auto-generated
confirmation of the receipt of my problem report, I have not heard anything
from them. I'm dismayed by their response considering that I have regularly
purchased their products since WindDVD 5.

I would appreciate it if anyone who has run across this problem and resolved
it would share how they fixed it.

TIA.