In this case you must revert settings (enable using JComments style) and then in /components/com_jcomments/tpl/default/style.css setup styles for these links.
There are 3 CSS classes for it:
.jcomments-links {margin-top: 10px; clear:both; text-align: left}
.comment-link, .readmore-link{padding: 0 5px 5px 14px;background-image: url(images/jc_blog.gif);background-repeat: no-repeat}
.comment-link {background-position: 0 -27px}
.readmore-link {background-position: 0 2px}
The 'jcomments-links' sets params for links container (such as margin and align) you can stay it without any changes.
All you need - replace lines:
.comment-link, .readmore-link{padding: 0 5px 5px 14px;background-image: url(images/jc_blog.gif);background-repeat: no-repeat}
.comment-link {background-position: 0 -27px}
.readmore-link {background-position: 0 2px}
with
.comment-link {/* put here style definition for comment link */}
.readmore-link {/*copy here style definition for readmore link from your template */}
Or you can go by another way and remove lines:
.comment-link, .readmore-link{padding: 0 5px 5px 14px;background-image: url(images/jc_blog.gif);background-repeat: no-repeat}
.comment-link {background-position: 0 -27px}
.readmore-link {background-position: 0 2px}
from JComments styles file and then change your template by adding '.comment-link' and '.readmore-link' to Readmore class definition in your template. For example search:
a.readmore {
and replace with
a.readmore, .comment-link, .readmore-link {
Or... last way.. you can edit /components/com_jcomments/tpl/default/tpl_links.php and replace
class="readmore-link" with
class="readmore"...