I have been using PD9 very succesfully for some time now - so theoretically no issues with it (I am not a very sophisticated user). I Have aWin 7 X64 I7 system with 9GB memory and an ATI 4870 Graphics card.
Having decided to recover video from some old VCR tapes via USB2863 converter, I then decided I would burn these to DVD. What happened however was that whilst I could produce MPG files using the software rendering (very very slowly!) I was unable to render using the hardware accelaration.
Windows 7 during one of its upgrades last week had upgraded Catalyst Manager to 11.11. So I decided to regress to 11.5 which I had had no problems with and all rendering working OK. I also installed the version of AVIVO released with 11.5.
I am not suggesting that there is any problem with 11.11 or PD9 they may work fine together on other systems but I have noticed a number of negative comments about the HD4870 and wonder whether this incompatibility is the cause - I know the 4870 is old but it still cuts the mustard on my system.

Hoping the above helps someone.

Don Gigabyte I7/4940 O/C 4.3, Noctua Cooler 10GB DDR3, 4 x 1TB, 1TB SSD, Geoforce GTX660 TI 8500W PSU, Windows 10 Pro 64bit.