Oksana, I don't understand what you want!
(1) When I download a photo into the gallery, at no time am I allowed to enter or change any information.
(2) Once the image is downloaded and part of the gallery, there doesn't seem to be any way to edit it to add a "description". The only option I have is the "delete" button below the image.
(3) I can go into my WordPress "media library", however. There I can see all images downloaded into the BWS gallery. I can also edit each to add a "description" or a "caption". But after adding both, neither the "description" nor the "caption" appears in the BWS gallery.
If I send you a screen shot of am image edit screen from the WordPress media library, it will show both a description and a caption.
If I send you a screen shot of the BWS gallery in view mode, you will see the images only.
If I send you a screen shot of the BWS gallery in edit mode, you will see all the photos, and each will have a delete button under it. There are no options to edit, or to insert a caption or a description.
I am not sending a screen shot because I don't know which one you want.
Can you please help, respond more quickly, and be clearer as to what I should do to make your program work?