You are unlikely to be able to upload an entire Juicebox gallery (retaining its folder structure) using a browser-based file manager. (Online file managers usually allow you to upload only individual files, not folders.)
You'll need FTP access to the web space that GoDaddy provides to you and you can then use a dedicated FTP program (such as Filezilla) to upload your Juicebox gallery to your web space with a single drag and drop action.

The CPanel instructions are for Linux Hosting but you mentioned Plesk so it sounds like you have Windows Hosting.
Here is GoDaddy's "FTP: Upload my files to Plesk hosting" support page (the second part of the document you attached to your last post). (They recommend Filezilla, too.)

I hope this points you in the right direction.
If you run into any problems with FTP on your hosting account, then your web host (GoDaddy) should be able to help you out.

It looks like you have copied and pasted the Juicebox embedding code at the very end of your 'Gallery' web page (just before the closing </body> tag).

The Juicebox embedding code (or more specifically the <div id="juicebox-container"><div> container) should be placed in your web page wherever you want the gallery to be displayed. The Juicebox embedding code should replace your existing gallery code but it looks like you might have just removed your existing gallery code and added the Juicebox embedding code to the end of the web page.

It looks like the Juicebox embedding code should go inside your <div id="imageGallerySimple_v11_0" class="xwidget simpleGallery"></div> container (but you might need to keep the 'id' and 'class' attributes intact in case there is some custom CSS on your web page which defines the dimensions of this container which you might want to retain).

Incidentally, embedding a Juicebox-Lite gallery is exactly the same as embedding a Juicebox-Pro gallery.

If you set showOpenButton="TRUE" (in JuiceboxBuilder-Lite's 'Customize' section), then the Open Image button will be displayed on the Button Bar.
When the Open Image button is clicked, the gallery will open the corresponding imageURL (the gallery image) in a new tab unless there is a linkURL specified for the image, in which case this will be used instead.
The linkURL can be a relative path (relative to the web page containing the gallery's embedding code) or an absolute path, in the form http://www.example.com/images/image_0001.jpg.

You can set a unique linkURL entry for each image on JuiceboxBuilder-Lite's 'Images' tab (just click a thumbnail to reveal the input fields at the bottom of the window).

(If you wanted to allow users to open images larger than those used in the gallery, then you could prepare larger images and point towards them using the linkURL entries.)

You could also set imageClickMode="OPEN_URL" (Pro only, via JuiceboxBuilder-Pro's 'Customize -> Main Image' section).
Now, when you click the main image, the linkURL (or imageURL if there is no corresponding linkURL) will be opened (instead of navigating to the previous or next image). Navigation can still be achieved via the navigation buttons.

I hope this helps.

JuiceboxBuilder does not read the image's EXIF orientation flag and dynamically rotate the image. It just displays the image (in the application's interface) as is. Also, when you allow JuiceboxBuilder to resize images when creating a gallery, all embedded metadata (including the EXIF orientation flag) is stripped from the image so the image in the gallery (displayed in a web browser) should be in the same orientation as it is in JuiceboxBuilder's interface. The image displayed in the gallery will have no EXIF orientation flag so no programs (such as web browsers) would be able to read such a flag and dynamically rotate the image.

However, it sounds like you might have deselected the 'Resize Images' checkbox, in which case JuiceboxBuilder would simply copy the source images across to the gallery's 'images' folder with all embedded metadata (including the EXIF orientation flag) intact and the web browser is reading the EXIF orientation tag and dynamically rotating the image in the gallery.
Regardless of the state of the 'Resize Images' checkbox, JuiceboxBuilder will always resize images (stripping out the metadata) for the thumbnails and this would explain why your thumbnails are oriented correctly (they do not have EXIF orientation flags) whereas some of your main images (which do have EXIF orientation flags) are not.

I can't be sure that this is what is happening but it sounds like it might be a possibility.

EXIF orientation can be a bit of a minefield at times and there seems to be little consistency in how the EXIF orientation flag is handled by different programs and platforms. This article (whilst a little out-of-date), gives a sense of how complex and confusing EXIF orientation can be.

One sure-fire way to avoid such problems would be to re-save your images (prior to feeding them to JuiceboxBuilder) in an imaging program (such as Adobe Photoshop) stripping out the EXIF metadata and, then, if necessary, rotate the images in JuiceboxBuilder's interface (via the rotate button near the lower right corner of the 'Images' tab after clicking the relevant thumbnail to reveal the input fields at the bottom of the window) so that it is visually oriented correctly.
I realise that this will add an extra step to your existing workflow but it should hopefully solve any orientation problems.

Otherwise, if you are not already doing so, just select the 'Resize Images' checkbox and allow JuiceboxBuilder to resize your images (making sure that the orientation is OK in JuiceboxBuilder's interface).

I hope this helps.

Unfortunately, the link you provided results in an error 404 (file not found) so I'm unable to see your gallery's web page.
However, it sounds like your problem may be specific to Drupal and the Juicebox module.
Please note that the module is an unofficial plugin which was not written by ourselves. As such, support for the module would be better directed towards the Drupal forum where the author of the module (who has a greater understanding of the module's code and the inner workings of Drupal) should be able to help you further.
I realise that this does not address your problem directly but I hope it at least points you in the right direction.

You're welcome!
I'm glad it worked. Thank you for letting me know.

I think all you might need to do is add the following line of code at the very end of (but still inside) your foreach loop:

$xmlRoot->appendChild($image);

This should create a valid XML file with correct opening and closing <juicbeboxgallery> tags and no need to perform any string manipulation on the resulting file.

@pantau

You could add the custom CSS to the template file that JuiceboxBuilder-Pro uses to generate the gallery's 'theme.css' file.
In doing so, the custom CSS will be included in all galleries created by JuiceboxBuilder-Pro.
Open the following file in a plain text editor and add the custom CSS to the bottom of the file.
Mac: /Applications/JuiceboxBuilder-Pro.app/Contents/Resources/template/jbcore/classic/theme.css
Windows: C:\Program Files (x86)\JuiceboxBuilder-Pro\template\jbcore\classic\theme.css

@pantau

There are currently no configuration options available to change the image title and caption font sizes (thank you for the suggestion) but it is still possible to do so (via HTML formatting or custom CSS).
Please see this forum post for details.

There's no way to specifically change the font size in JuiceboxBuilder-Pro's interface.
You could, however, change the scale of your computer's display.
If you are using Windows 10, then you could "Change the size of text, apps, and other items" in 'Settings -> System -> Display -> Scale and layout'. You could try changing the value from 100% to something like 125% (even temporarily whilst using JuiceboxBuilder-Pro).

If you follow the regular Embedding in a HTML Page instructions, you'll need to:

This means that you need to upload the gallery files to your web server, usually using a dedicated FTP program such as Filezilla.
Please check with SiteSpinner to make sure that they allow FTP access to the web space that they provide to you and, if so, to get the credentials that you'll need to log in via FTP (host, username, password).

If SiteSpinner does not allow FTP access on your hosting account, then you'll need to find an alternative host for your Juicebox gallery and you can then follow the Embedding in a Web Template Site instructions.

There are many web hosts that offer free web space which would be suitable for hosting Juicebox galleries. (Juicebox galleries do not require any special web server requirements, with the exception of Password Protection and the Download Button which require PHP 5.2.0 or later. Please see the System Requirements support section for details.)
Try a web search with terms such as 'free web hosting' but please bear in mind that with a free hosting account, you may get little or no support, less reliability (more server down-time) and fewer features.
A few free web hosts that you might like to take a look at are 000webhost, hostinger and x10hosting.
Please note that we are not affiliated with any of these web hosts at all. They are merely suggestions (and not recommendations).

I hope these notes help to clarify things.
Please let me know if you have any further queries and I'll do my best to answer them for you.

I'm glad that you've been able to resolve your problem.
Thank you for letting me know.

I have found your Juicebox "Birds" gallery here http://www.sieg.be/page26.html and it displays and functions fine when I view it in my own browser.
If you are still seeing the "Juicebox Error: Config file not found." message, then try completely clearing your browser's cache before reloading your gallery's web page.
(You could also try viewing your gallery in a different browser (Chrome, Edge, Firefox, Internet Explorer, Opera, Safari) so see if this makes a difference.)

Incidentally, your gallery's web page has stray closing </div> tag (just before the closing </body> tag) which should be removed (but I do not think that this is likely to be causing your problem).
You can check your web page for HTML errors with the W3C Markup Validation Service. Any errors reported should ideally be fixed. Once the code on your web page validates correctly, your web page should be rendered with greater predictability and consistency across different browsers.

Hopefully clearing your browser's cache will resolve your problem.