The URL you indicate above is a media item within an album.
If it has a title of "Imported Item" then it means it did not have a title in XenGallery to begin with. Titles are required in XenForo Media Gallery so that title is used instead if one doesn't exist in XenGallery.
The title can be changed to 'Something Else' with a simple database query (change accordingly):
SET media_title = 'Something Else'
WHERE media_title = 'Imported Item'
You can also edit them by hand with Inline Moderation.