Maybe I'm a bit dim, but I didn't know you needed MPEG-2 Activation for Transcoding from AVI to MPEG-2, for DVD. Importing & Exporting MPEG2 File - Yes.
Have you tried entering your existing Actvation Key?
If you have Nero Burning ROM-SE? Create a Disk Image & Burn DVD with that. Or if you have NeroVision Express, Render to File DV-AVI & Import that into NVE & go straight to Burn.
In any event, Pinnacle's Rep Marc P, who Posts on the Forum, should sort this out for you, I would have thought.
If you do need a new MPEG-2 Activation Key IMO, Pinnacle's excuse that they no lomger support S8/9 won't wash. Since you have purchased a Standalone product, which is common to all Versions of Studio & not just S8/9..