Yes. You can remove all titles in a single action in JuiceboxBuilder-Pro by going to 'Images -> Titles -> Use None' from the drop-down menu at the top of the application.

I have viewed your web page in several browsers (IE10, Firefox 20.0, Chrome 26 and Safari 5.1.7) on my PC and do not see any galleries at all (due to your modification of the 'juicebox.js' file).

There is no reason why you should not be able to display 4 Juicebox galleries on the same page.
I regularly use jAlbum and the Juicebox Skin to create multiple-gallery albums (with a JavaScript tree menu which switches out many more than 4 galleries on the same page).

I have tried using the JavaScript you posted with 4 of my own test galleries and all worked fine. I can continually switch between all 4 galleries and have not yet been able to replicate the problem you describe. The only problem I encountered was when resizing the browser window and not refreshing the page (where the layout is incorrect) but this can be solved by setting the dimensions of your 'juicebox-content' divs using inline CSS (as documented in the 'Using Percentage Heights' section here).

Although my testing shows that your code seems to work OK, you might like to try using the Juicebox-Pro API's showGallery() method to show/hide your galleries.
Alternatively, you might like to try loading each gallery as it is selected (as the Juicebox Skin for jAlbum does) rather than load all your galleries at once and then hide/show them selectively.

Once you get your web page back up and running (by reinstating the 'juicebox.js' file to the stock version from Juicebox-Pro v1.2.0), please post back so that I can take a look at your web page for myself and please let me know what browser(s) you see this problem in.

No. The Lightroom plugin comes bundled with Juicebox-Lite and you can upgrade the plugin by replacing the Lite 'jbcore' folder with the 'Pro' version but the structure of the output files is exactly the same whether you use Juicebox-Lite or Juicebox-Pro.

No problem. I am glad that you have been able to solve your problem.
Thank you for posting back to let me know.

I have just noticed that there looks to be a problem with your gallery's 'juicebox.js' file on your web server. There is a lot of extraneous content at the end which is likely to be causing your gallery to fail to display.
Try re-uploading your gallery's 'jbcore' folder to ensure that all files are present and correct.

This is certainly possible.
Take a look at the View Resizable Gallery with Top Menu Example in the Embedding Multiple Galleries section of the Embedding Guide.
If you view the source of the web page in your browser, you should hopefully see how the example works.
You can then copy and modify the code to suit your needs.

An automated solution would be to create a multiple-gallery album using jAlbum and the Juicebox skin.
When using jAlbum and the Juicebox skin, you can drag and drop a complete folder structure into jAlbum's main window and click 'Make Album'.
The resulting album will have a separate Juicebox gallery for each and every folder/subfolder in your input structure and all the galleries will be linked together via a JavaScript navigation tree (displayed on the left of the screen). On clicking a link for a gallery, the current gallery is replaced with the newly selected one.
Here is a sample album created by jAlbum and the Juicebox Skin.

Yes. If you already have an existing .htaccess file, you can just add the code to the file.

Using the following code (as you do) will horizontally center the gallery in its parent container.

<div id="juicebox-container" style="margin: 0 auto;">

However, you may then need to horizontally center the gallery's parent container in its parent container.
Your gallery seems to be nested within 7 further <div> containers and an <article>.
Looking at your web page, it looks like you may need to horizontally center the <div class="entry-content"> within the <article class="post-13 page type-page status-publish hentry"> (using the same method as before).

For your own website's galleries, try creating an .htaccess file containing the following code and upload it to your website's root directory. (Please note that this requires an Apache server and is untested.)

<IfModule mod_headers.c>
Header set Cache-Control "no-transform"
</IfModule>

You could also contact your 3G provider to see if it is possible for content modification to be turned off on your account.

Yes. There is a similar FAQ for SimpleViewer here. Unfortunately, content modification breaks many websites that uses JavaScript, not just Juicebox and SimpleViewer galleries.

It sounds like you are using WP-Juicebox (the Juicebox plugin for WordPress) so hopefully the following information will be relevant.

When creating a gallery with WP-Juicebox, the plugin uses the Media Library image's 'Title' for the Juicebox 'Title' and, by default, WordPress populates the Media Library 'Title' fields with the image filenames.

If you would like to use the post's title for the Juicebox 'Title' in an individual gallery, then you could edit each gallery image in your Media Library and paste the post's title into the 'Title' fields.

Otherwise, if you wish this change to happen globally for all galleries you create (without the need to change the 'Title' fields on individual images), then open the 'wp-juicebox/config.php' file in a plain text editor and change line 69 to the following:

$title_text = $new_dom_doc->createCDATASection(get_the_title($post_id));

Please note that the line number above refers to WP-Juicebox v1.2.0.1.

Thank you for sharing your solution.
That seems to work well across all browsers (and versions of Internet Explorer).
It would be great if valid code was rendered identically in all browsers but this is not always the case, especially in older browsers.

So far, I have been unable to create a stripped-back test case which fails in IE8 by nesting the 'juicebox-container' <div> in multiple parent containers. As long as all the parent containers have heights specified by inline CSS, the gallery is displayed at the correct height in IE8 (and other browsers).