I requested this nearly two years ago in the hope that it would appear in a subsequent version, and it now has, so thank you!
Drag and drop speeds up many aspects of working in many packages, not least of all in this area of PTE AV Studio. It will be popular.
Another area for consideration, also previously requested, where drag and drop would be helpful, is in the management of styles and themes, so maybe this could be added to a to-do list in the future.
Regards
wideangle