Base on this discussion, I changed the sign up link in comments from this:

to this:

I add a red border and icons and you get a very big area to click.

Here is the icons image you can use:

Or you can do a better one with www.iconfinder.com

Now is the CSS code put in the advanced CSS field of Design Studio:

.comment-join a {

   display: block;

   height: 24px;

   padding: 0.5em 0 0 1em;

   border:1px red solid;

   background: url(http://api.ning.com/files/.................../signupicons.jpg) 100% 50% no-repeat;}

It's kind hard to change non-member display area. Cause I need to open two different browsers, one sing in and one not. And crazy browser cache issue. Usually you can push ctrl+F5 or shift+F5 to prevent browser cache when refresh but I don't know what keys in Mac. I try shift+command+R in chrome but doesn't work.

And don't forget to change to a nice wording asking to be a member.

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