If you are using fotoShare and it already has photos from your last event or would like to clear the existing photos, you can do the following:
Go to Settings > Sharing and change the album name.
Change Album's Name under dslrBooth > Preferences > Album Name
Please keep in mind that fotoShare will only download images from the last 24 hours for your latest album.
It is not possible to delete multiple photos at once from the album?