OK, thanks.
If you still have problems, just post the link to your gallery and I'll take a look at it for you.

thumbsPosition is in the 'Thumbnails' section of the 'Customize' tab.
You need to be on the 'Images' tab (to the left of 'Customize') and then click the 'Change Sizes...' button in the 'Image Size' control panel (on the left side of the window). See the image attached.

If your have a full page gallery (i.e. it has dimensions of 100% x 100% and there is no other content on the web page), then the Expand Button will only be visible if you set useFullscreenExpand="TRUE" in JuiceboxBuilder-Pro's 'Customize -> Lite' section (for the gallery to expand to fill the user's entire screen). If useFullscreenExpand="FALSE" (the default value), then the gallery would expand to fill only the user's browser window (not the entire screen) and, as the full page gallery already fills the browser window, it would not be able to be expanded any larger so Juicebox hides the Expand Button.

If this does not explain what you are seeing, then please post the link to your gallery's web page so that I can see the problem for myself and hopefully help further. Thank you.

You can change the thumbnail dimensions using the thumbWidth and thumbHeight configuration options.
For reference, a list of all Thumbnail Options can be found here.

When creating a gallery with JuiceboxBuilder-Pro, you can set the thumbnail dimensions on the 'Images' tab. (Just click the 'Change Sizes...' button in the 'Image Size' control panel to reveal the input boxes.)
Thumbnails will be generated at the specified dimensions and the thumbWidth and thumbHeight options will automatically be set in the gallery's 'config.xml' file accordingly.

Alternatively, just set the thumbWidth and thumbHeight options in your gallery's 'config.xml' file to whatever values you like (instructions on how to set configuration options can be found here) and, when the gallery is displayed, Juicebox-Pro will dynamically scale the thumbURL images to fill the chosen dimensions. (Please note that if your thumbURL images do not have the same aspect ratio as that set by the thumbWidth and thumbHeight options, cropping will occur.)

I'm glad that clearing you browser's cache solved your problem.
Thank you for letting me know.

When I view your gallery's web page in a desktop browser, I see the thumbnail paging arrows being displayed (to the left and right of the thumbnails, centered vertically).
If you do not see this yourself, then try clearing your browser's cache before reloading the web page.
If you have made any changes to your gallery recently, your browser may still be using an older, cached version of your gallery's 'config.xml' file instead of the latest version from your web server.

@gfs

The issue reported above was addressed by the developers, confirmed as fixed (via email) by the original poster (robertcoldwell) and the bugfix was included in Juicebox v1.5.0 (which was released on 24 May 2016).

It certainly seems strange (though not impossible) that the problem would crop up again over a year later in a different version.

One thing I notice which could be causing layout problems is that there are several HTML errors on your web pages, including stray and unclosed <p> and <span> tags (and extra double-quotes alongside certain <div> attributes). Also, your gallery <div> containers are inside <p> tags. (A <p> element should not contain another block-level element such as a <div>.)

Try validating your gallery web pages with the W3C Markup Validation Service and fix the errors reported.
Once the code on your web pages validates correctly, the web pages should be rendered with greater consistency and predictability across different browsers and devices.

Unfortunately, I do not have access to an iPad Pro so cannot check your web pages in such a device myself.
If, after fixing the HTML errors on your web pages, you still see the problem, then I'll happily compile a report for the developers who will investigate further but it would help to have as much information about the problem as possible so please let me know the following (if you can).

(1) What version of iOS was the iPad Pro running?
(2) What browser or browsers (Mobile Safari, Mobile Chrome or any others) did you see the problem in?
(3) If you can gain access to the iPad Pro again, please provide a screenshot of the problem (and let me know which of your galleries it is from) so that we can see exactly what you are seeing.
(4) Also, if possible, please let me know if the problem occurs in any of our demo galleries here.

Thank you.

It is not possible to change where JuiceboxBuilder initially puts its own presets folder when the application is installed but you can copy the default preset files (and save your own) to anywhere you like.
You can then load a preset from the new location via 'Presets -> Load Preset...' from the drop-down menu at the top.
Likewise, you can save a custom preset to anywhere you like via 'Presets -> Save Preset...'.
The dialog window for loading and saving presets should remember the last used location each time it is opened.

Please note that the 'Load Preset' combobox (just above the 'Lite' configuration options) will always read the preset files from the original installed 'Documents' location. This cannot be changed.
If you want to store presets in a different location, then you'll need to use the 'Load Preset...' and 'Save Preset...' options from the drop-down menu at the top.

According to your gallery's 'config.xml' file, the 1st image in your gallery should be located here:
http://www.zw-g.de/slides/zeiterfassung … modell.jpg

However, going directly to that location in a browser (bypassing Juicebox) just redirects to your home page, suggesting that the image is not present on your web server (or at least in the correct location).
Please check that your gallery's 'images' and 'thumbs' folders have been uploaded to your '/slides/zeiterfassung-module/' directory.

If the images are in their correct location on your web server, then please check their permissions to ensure that they are not too restrictive. Default file permissions of 644 should be fine. You should be able to check and change permissions using either a dedicated FTP program such as Filezilla or via your web hosting account's online File Manager.

I hope this points you in the right direction.

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

For anyone else encountering the "The application cannot be installed due to a certificate problem." message whilst installing JuiceboxBuilder, the solution is usually to completely uninstall the existing version of JuiceboxBuilder first before installing the new version. (For reference, this is noted in the 'Installation Issues' section of the JuiceboxBuilder User Guide.)

I'm not sure why this did not work for you when you first tried it but I'm happy to hear that all is well.

You're welcome!

Please feel free to post suggestions for future versions in the Feature Requests forum thread.
This keeps all the ideas together and ensures that they are not overlooked by the developers.
Thank you.

I'm glad you've found a suitable workaround for your problem.
Thank you for letting me know.

Unfortunately, there is no automated method for converting multiple SimpleViewer galleries to Juicebox galleries in bulk.

You can swap each gallery's 'svcore' folder for a jbcore' folder (which shouldn't take too long) and Juicebox can read a SimpleViewer gallery's 'gallery.xml' file so you wouldn't need to alter the contents of the configuration file (although you'd need to rename it to 'config.xml' or add a configUrl to the Juicebox embedding code) but actually changing the embedding code in your web pages is likely to take up most of the time in the conversion process.

Depending on how your website is structured (and whether or not you use a baseUrl for your galleries), swapping the embedding code over for all your galleries could be a relatively easy process of copying and pasting (but, admittedly, if you have many galleries, it could be quite time consuming).

Also, please bear in mind that although Juicebox can read a SimpleViewer gallery's 'gallery.xml' file, Juicebox was written from the ground up (and is not just a HTML 5 translation of SimpleViewer). As such, Juicebox has a different feature set to SimpleViewer and not all SimpleViewer configuration options have direct equivalents in Juicebox. With this in mind, you might like to use JuiceboxBuilder to convert your SimpleViewer galleries (as documented in the Converting a SimpleViewer Gallery support section) as you could tweak your galleries via the JuiceboxBuilder interface during the conversion process.

On the web page where the gallery does not appear, there is the following line of code:

<script src="/plan-a-visit/washed-ashore/globalassets/juiceboxgalleries/NewWashedAshoreTest/jbcore/juicebox.js"></script>

However, there is no 'juicebox.js' file in that location.
If you change the line above to the following, then the gallery should appear:

<script src="/globalassets/juiceboxgalleries/NewWashedAshoreTest/jbcore/juicebox.js"></script>