[Plugin: NextGEN Gallery] How is meta data pulled

i’m trying to figure out why some of my photos get imported with the correct descriptions and others do not.

from what i can tell, all of the meta for my pictures appears the same in photoshop. but when i import to nextGen, some pics have the descriptions and others have blank space where the description should be. when i view the meta in nextGen, both pictures have the descriptions/captions/title showing in the EXIF, etc.

where exactly does the description info get imported from when it goes into nextGen? we use Photoshop CS2 and Adobe Bridge.