Brandon,
The Grafpaks that contain actual images vs generated media do indeed suffer when imported to an HD timeline. By and large, the majority of the Paks don’t use graphics.
Either way, open them up in an HD timeline, check the “Match Aspect Ratio” box, and you’ll be set with regard to the generated media-type lower thirds.
Douglas Spotted Eagle
VASST
Aerial Camera/Instructor
Certified Sony Vegas Trainer