Your problem is almost certainly with setting your gallery's height to 100%.
The following FAQ explains the problem. (Your gallery displays fine in IE11 but not in Firefox 35.0.)
My gallery does not show in Firefox or gets cropped to a small height. Why?
When you set a gallery's height as a percentage, you must ensure that all the gallery's parent containers have heights specified via CSS, otherwise SimpleViewer will not be able to calculate its actual height. For example, when setting a gallery's height as 100%, SimpleViewer needs to know what its height should be 100% of.
Please see the note regarding 'Using Percentage Heights' in the Embedding into a HTML Page support section.
A quick fix would be to set your gallery's height to be a fixed pixel value rather than a percentage (changing the height Embed Code Parameter value).
Try changing your gallery's simpleviewer.load() line from:
simpleviewer.load("sv-container", "100%", "100%", "FFFFFF", true, null, null, null, false);
... to something like the following:
simpleviewer.load("sv-container", "100%", "600px", "FFFFFF", true, null, null, null, false);
This should solve your problem.
If you set the gallery's height in svBuilder-Pro (in the 'Customize -> Embed Options' section) to something like '600' or '600px' (either will work fine), then this height should be used in the Embed Code on the 'Publish' tab and in the embedding code within the gallery's 'index.html' file.
SimpleViewer Support Team