maybe i am just stupid but i think that if you are able to drag assets to a project it should recognize them. I also think that if you want to add a whole folder to a project you should not have to add each individual file/asset within that folder.
You might have more luck posting this on the Corona Project Manager board:
http://forums.coronalabs.com/forum/537-corona-project-manager/
You might have more luck posting this on the Corona Project Manager board:
http://forums.coronalabs.com/forum/537-corona-project-manager/