If I understand correctly what you are looking to do, we don't have a way to transfer images directly from Photobucket to Auctiva. If you have your images on your hard drive, you can upload them to Auctiva using the image uploader.
We don't have a bulk method to transfer images from Auctiva to your local computer...but..you can go to the manage image page, click on the thumbnail of each picture you want to save to expand it to full size, then right click with your mouse on the expanded pic and do a save to your local computers hard drive. As I say, not a bulk method but try it...goes faster than it sounds and will get the job done.
Hope that helps.