The following text causes Scrivner to freeze. I have added some markup to make the construction clear. I’m not sure if the LINEBREAK is in the CAPTION or after it. This can’t be seen in Scrivner.
<$img:articles/The Perils of Woods Travel/01 Baby beaver 1170x1654.jpg;ebook=80%>
<CAPTION>
Baby beaver sleeps contentedly on friend’s shoulder —Photo National Parks Branch
<CAPTION>
<LINBREAK>
<PAGEBREAK>
<$img:articles/The Perils of Woods Travel/02 Maine Porcupine 1170x982.jpg;ebook=80%>
<CAPTION>
The inquisitive porcupine will provide sustenance for a hungry “lost man” until the relief party arrives
<CAPTION>
The cuprit is the combination of LINEBREAK and PAGEBREAK. Changing the LINEBREAK to a return fixes the problem. Or removing the PAGEBREAK. Otherwise Scrivner freezes and has to be killed.