You have to download all the images then supply the client with a promotion code to deduct the full amount.

So say you have the digital images set at 10.00 a piece and there are 10 images in the gallery. You would add them to cart and the subtotal/ total would amount to 100.00 . Then you would supply a promotion code to the client for an amount of 100.00 off which would zero out the order and allow them to checkout and download without paying.

The missing functionality to this which i have requested but we have not received is the ability to zip up all the downloads and provide one link to download. Currently the checkout will supply a download individual link for each image. So the client would have to click on 10 links to download 10 images. 10 would not be that painful however a gallery of say 40 and the clients would most likely complain.

I hope this helps.