I'm on plugin version 1.5.1. When I add text with double quotes (") to the "Before / after related entries" settings and save, then the double quotes become slash-double-quotes (\").
For example, if I enter:
<div class="related_posts">Related posts:<ol>
After saving, the text becomes:
<div class=\"related_posts\">Related posts:<ol>
This makes it so that CSS cannot refer to this div tag. The current work around to get CSS to recognize this tag is to omit the double quote (non-XHTML1.0 compliant) like so:
<div class=related_posts>Related posts:<ol>
and pray that the user's browser supports it.