I haven't purchased this product yet, so apologies for posting this in the forum.
No problem at all!
Is there a download feature built into the product?
Please see this FAQ:
How do I allow or prevent users from saving gallery images?
It is not possible to right-click and save an image in a Juicebox gallery (and there is no direct download functionality) but what you could do is set showOpenButton="TRUE" (in JuiceboxBuilder-Pro's 'Customize -> Lite' section) to display the 'Open Image' button on the Button Bar. When the button is clicked, the image will be displayed in a new tab and can be downloaded via the browser's right-click 'Save Image As...' option.
It would be much easier to implement direct download functionality if all browsers supported the HTML 5 'download' attribute but this is not yet the case. Please see here for a list of browsers which currently support this feature.
If you would like to try this (though it will only work in the browsers listed in the link above), you could include a link within each image's caption using the 'download' attribute such as the following:
<a href="images/wide.jpg" download="wide.jpg">Click here to download image.</a>
The href="images/wide.jpg" part is the path to the file which will be downloaded. You can use an absolute path (such as 'http://www.example.com/gallery/images/wide.jpg') or a relative path (as in my example above). If using a relative path, it will be relative to the HTML page containing the gallery's embedding code.
The download="wide.jpg" part is the name which will be given to the file when the user downloads it. (It does not have to be the same as the image's filename, although it should have the same file extension.)
The Click here to download image. part is the text that will be displayed on screen as the caption which, when clicked, will download the file.
Please remember that this will only work in certain browsers and visitors to your web site using browsers which do not support this HTML 5 attribute (such as Internet Explorer and Safari) may wonder why this feature in your gallery does not work as expected. (You may wish to add a note somewhere on your web page to say that direct download functionality is available only in Firefox, Chrome and Opera.)
The suggestions above will work equally well with Juicebox-Lite (the free version) and Juicebox-Pro so you could try things out with Juicebox-Lite before purchasing Juicebox-Pro.
Juicebox-Lite can be downloaded from this web page.
I hope this helps.