I know they land in different folders; but I'm going to upload several photo albums. This is why I have been editing the Index.html file name. So when I set up my main home page with links to the right photo album.
The folders will take care of that. The link to the album about your dog would be:
<a href="mydog/index.html">
And the link to the album about your cat would be:
<a href="mycat/index.html">
Renaming the index page is an unnecessary step.
In any event, I think Laza is absolutely correct - your pages are being fed through some sort of "page optimization" script before they're served to the site visitor, and that is what's causing them to fail.
ETA: BTW, since index.html is the default name for a page on the web, the link to your album, instead of being this:
http://www.ringelstetter.net/Holy_Land_2013/holy_land_2013.html
Would be just this:
http://www.ringelstetter.net/Holy_Land_2013/