Is the example blog yours? If so, there are some odd things in your HTML and CSS. Image tags don't have ending tags like </img>, and instead, they just need a / at the end of the tag like this:
CODE
<img src="http://www.japanwindow.com/gallery/mti/040210.jpg" />
And I don't know what xthumbnail-orig-image is, its not a standard html attribute that I know of.
To make images line up next to each other, here's what I do. Put this in your entry:
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<div class="photos"><img src="http://my-site.com/image_one.gif" alt="image_one" /><img src="http://my-site.com/image_two.gif" alt="image_two" /></div>
<br clear="all" />
and this in your css:
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.photos img { float:left;}
The br after the images ensures that they don't make the text below them float around them.
Hope that helps,
Kristine