Unfortunately, it is not possible to load an existing gallery in Lightroom (or any of the other plugins).
Existing galleries can be opened only in JuiceboxBuilder-Pro.

Glad you like it (and thanks for the tip regarding Instagram and Flickr)!

The quickest and easiest way to delete all linkURL entries from a gallery's XML file in a single action would be to use the global search and replace functionality of a text editor.

For example, you could use Notepad++ (free) and do the following:
(1) Open your gallery's XML file in Notepad++
(2) Go to 'Search -> Replace...' from the drop down menu at the top to bring up the 'Replace' window
(3) Select 'Regular Expression' Search Mode
(4) In 'Find what' enter: linkURL=".*?"
(5) In 'Replace with' enter: linkURL=""
(6) Click 'Replace All'
(7) Go to 'File -> Save' to save your file

This will replace all linkURLs (even if the entries are different to one another) with blank/empty linkURLs (and the gallery will automatically use the imageURLs as the linkURLs).

Please check the linkURL entries in your gallery's XML file.
The 'Open Image' button opens the corresponding linkURLs. In order for the images to be used, the linkURLs must either be the same as the imageURLs or empty (in which case Juicebox will use the imageURLs by default).
It sounds like you might currently have the URL to your home page as your linkURLs.

It looks like you have entered the embedding code into your 'juicebox_gallery.html' page correctly. (It is being treated as HTML code rather than plain text so that's OK.) However, the path to the 'juicebox.js' file is incorrect.

Your gallery would display OK if you left your embedding code exactly as it is and just copied the contents of your gallery folder into the same directory as the page containing the embedding code (your root directory), following the embedding instructions here.

However, as you have already uploaded your complete gallery folder to your web server, you could leave the gallery files exactly where they are and use the baseUrl method of embedding (to point towards the gallery folder) as documented here.
Your embedding code would become:

<!--START JUICEBOX EMBED-->
<script src="/hotelmandarina_juicebox/jbcore/juicebox.js"></script>
<script>
new juicebox({
    baseUrl: "/hotelmandarina_juicebox/",
    containerId: "juicebox-container",
    galleryWidth: "100%",
    galleryHeight: "100%",
    backgroundColor: "rgba(255,204,102,1)"
});
</script>
<div id="juicebox-container"></div>
<!--END JUICEBOX EMBED-->

Either of these suggestions would work fine. I would recommend using the baseUrl method as it allows you to keep your gallery files inside the gallery folder which might help to keeps things organized on your web server.

That file would be useful only if you wanted to display the gallery on a page of its own. If you are embedding your gallery in another web page (and do not want to display the gallery on a page of its own), then you can safely delete your 'juicebox_index.html' file.

A couple of other notes which might help:
I notice that your 'juicebox_gallery.html' web page is missing several end tags (for example there are no </body> or </html> tags). You might like to check the code on your web page with the W3C Markup Validation Service and fix the errors reported. Once the code on your web page validates correctly, the page should be rendered with greater predictability and consistency across different browsers.
Also, if you choose to embed your gallery with a percentage height (such as 100%), be sure to give all of your gallery's parent containers heights via CSS as Juicebox will need to know what its height should be 100% of. If you find that a percentage height is giving you any trouble (it may not), then you could always just give your gallery a fixed height (such as 600px) instead.
Also, please see this note regarding Using Percentage Heights.

We don't always post a blog entry for each new release but we did announce the new version with a Tweet.
Follow us on Twitter and you'll be notified of new releases: https://twitter.com/juiceboxgallery

Otherwise, keep an eye on the Version History page which is updated when a new version is released.

I think I've found the root of the problem.
Juicebox will scale up the thumbnails on a thumbnail page on a mobile device if the following conditions are met.
(1) The gallery has dimensions of 100% x 100%.
(2) There is no existing viewport tag on the web page.
(3) The gallery is the only content on the page.

However, your web page created with jAlbum has the following line of code <div id="jalbumwidgetcontainer"></div> meaning that the gallery is not the only content on the page and so the thumbnails are not scaled up.
Your other gallery which functions correctly does not have this jAlbum widget container in it.

If you remove the jAlbum widget code from your web page, your gallery should hopefully display as expected.
If you don't use jAlbum widgets, try editing the skin's 'skin.properties' file and change the value for autoWidgetInjection (on line 2) from true to false . Then reload the skin and remake your album.

This would certainly be possible.
Please take a look at this forum post which demonstrates how a gallery's XML file can be generated dynamically when the gallery is displayed.
Rather than immediately output the XML data (via PHP 'echo'), you could modify the code to save the XML data to a file (ideally named 'config.xml' so that you do not have to change anything in a default gallery setup). Knowledge of PHP would be required.
You could then set up a Cron Job (scheduled task) on your web server to run the PHP script (to update the XML file) once a day. (Your web hosting account's cPanel might have a Cron Job interface which would make this very easy to achieve.)
I hope this points you in the right direction.

I've tried to replicate the problem using the same HTML page that you currently use ('/Emma-pictures/index.html'), the same gallery structure (a gallery created by jAlbum) and a gallery containing well over 140 images but I cannot get the 140-thumbnail display on either Mobile Safari or Chrome. The scaled-up 6-thumbnail display is always shown.

Your web page seems to load a little slower than my own test gallery.
I'm not sure if this is because of the problem (having to load 140 thumbnails) or the cause of the problem (perhaps a timing issue).
Do you have access to a different web server where you could temporarily upload the same gallery to see if things are different on another server? This might help in troubleshooting the problem.

I noticed the reference to WordPress on the Bluehost support page but your hosting account might have been using Varnish regardless of whether or not your hosting account was optimized for WordPress so it was worth a shot.

As I noted with the query string trick, the new file (without the viewport tag) is being served OK when a unique URL is used and the problem is not seen when this version of the page is used so the problem certainly seems to be a caching problem (removing the viewport tag appears to resolve the original problem you reported).
When I see the problem and view the source of the page, the viewport tag is present (even though it has been removed from the file on your web server) so the old version is still being served from somewhere.

Try viewing your web page in a different browser (such as Mobile Chrome) which has never been used to view the page before (if possible). If you still see the problem (now that the new file without the viewport tag is in place on your server), then the caching problem is server-side rather than client-side (in the browser). Perhaps you could contact your web host and ask if caching is present on your hosting account and, if so, how to turn it off.

Maybe a workaround would be to name the new version of your page 'index.htm' (rather than 'index.html').
The server should still hopefully be configured to find and use this file name as a default if a user navigates to the parent directory (without explicitly using the index file name).
As the filename is different, the old cached 'index.html' file should not be used.
(The only disadvantage would be that if you have any links to this page, you would have to adjust them accordingly.)

I cleared my iPod Touch's cache in the same way that you cleared your iPhone's cache.
I then loaded your 'Emma-pictures' gallery and still saw the problem myself. However, when I viewed the source of the web page, I noticed that the viewport tag was still present.
I then tried viewing the web page adding a (redundant) query string to try to force the new version of your page to be fetched from your web server and it worked.
I used this URL http://www.billanddot.com/Emma-pictures … ml?xyz=123 and only 6 thumbnails were displayed on the page (as expected). When I viewed the source of the web page this time, the viewport tag was not present.
It looks like the problem is solved by removing the viewport tag but that there is a caching problem somewhere along the line (forcing the old version of the page with the viewport tag still in place to be used). The caching may be happening server-side rather than in the mobile browser.

It looks like Bluehost uses Varnish caching. Try turning it off following the instructions here.

Alternatively, if you have an Apache server, you might like to try adding the following line of code to the .htaccess file in your root directory.

Header set Cache-Control "max-age=0, private, no-cache, no-store, must-revalidate"

Hopefully one of these suggestions will help.

Without seeing your gallery's web page, I do not know whether or not the extra space you refer to is actually part of the gallery.
If it is, then please see this FAQ which might help:
My Juicebox gallery shows too much space above or below the main image, how do I fix this?

If you set imageScaleMode="FILL" (even just for testing purposes) and the space is no longer there, then you could either leave imageScaleMode="FILL" (or imageScaleMode="SCALE") to fill the image area or reduce your gallery's height so that the aspect ratio of the gallery's image area better matches the aspect ratio of your images (resulting in less space when the images are scaled to fit within the image area).
If, when setting imageScaleMode="FILL", the space is still there, then it is not originating from the gallery and you might need to look elsewhere on your web page to see where it is coming from. Check the source code of your web page (usually via 'Right-Click -> View Page Source' or 'Tools -> Web Developer -> Page Source) to see if there are any empty <p> tags or <br> line breaks above your gallery which might be causing the space you see.

If you continue to experience difficulties, then please post the URL to your gallery's web page so that I can see the problem for myself and hopefully help further. Thank you.