Thanks for sending your document. I think that one of the lessons here is that float layouts are tricky. Personally, I would try to avoid floating anything except for images that you want to float next to text. An alternative in this case would be to use a flexbox layout, with wrapping turned on for the flex container. That will be much easier in the next version of Xway, because we are planning to support flexbox layouts directly (no need to use extended properties).
Having said that, here’s how you can fix this issue, while continuing to use floats. The box that is causing the problem is the Africa 2010 box. If you delete that box, the problem goes away. That’s also a general debugging tip: if you have a problem, see if it goes away after you delete things (don’t do this in your actual document - make a copy (File/Duplicate) and use that to experiment).
So what’s different about this box compared to the other boxes? If you look in Xway’s HTML view, you can see that this box is defined as:
<figure id="africa2010">
<p class="style10"><img id="kirkmans_310810-1027" src="resources/6_kirkmans_310810-1027-edit-edit-2.jpg" alt="" title="Africa 2010"> <span class="style12"><span class="style13">Africa 2010</span></span></p>
</figure>
Within the box there is a single paragraph that contains the image and text. The other boxes contain two paragraphs: one containing the image, and another containing the text. E.g.
<figure id="bristlecones2010">
<p class="style10"><img id="bristleconepines-8623" src="resources/02bristleconepines-8623-edit.jpg" alt=""></p>
<p class="style11">Bristlecone Pines 2010</p>
</figure>
So what you want to do is to add a paragraph before “Africa 2010”: select the lion image, and use the right arrow to put a text cursor after it, then press Return (you could also delete the space that currently occurs before the text). Then, change the top margin of this paragraph to zero (as in the other boxes), and tidy things up a bit by deleting the spans (selecting the parent africa2010 box, and choosing Flatten from the Format menu will do this). Finally, put a cursor back in “Africa 2010” and set the text size to Small in the Paragraph Inspector (again, matching the other boxes).
Now, if you preview your page, you should find that it displays correctly.
I don’t exactly know why this fixes the problem, but (as I said) float layouts are tricky - and that’s one of the reasons Xway doesn’t yet support them directly.