WordPress.org

• Instructions on how to use the plugin: http://wordpress.org/extend/plugins/list-category-posts/other_notes/ - Read it.
• Template system how to customize the way the posts are shown: http://wordpress.org/extend/plugins/list-category-posts/other_notes/. I am aware the Template System is not really friendly right now, I'll work on this whenever I get the time to work on the plugin for a while.
• New feature requests, Bug fixes, enhancements - You can post them on GitHub Issues.

• Questions If you have any usage questions, go to WordPress Answers for support. It's a great place with a large community of WordPress users and developers. Just ask your question using the 'plugin-list-category-post' tag.

• FAQ

Since version 0.18, this plugins does not work on servers with PHP 4. If you're still using PHP 4 on your webhost, you should consider upgrading to PHP 5. WordPress 3.1 was the last version to support PHP 4, from 3.2 and forward, only PHP 5 is supported. You can still download an older version of the plugin if you're using PHP 4.

Plugin could not be activated because it triggered a fatal error. Parse error: syntax error, unexpected T_STRING, expecting T_OLD_FUNCTION or T_FUNCTION or T_VAR or '}' in /.../wp-content/plugins/list-category-posts/include/CatListDisplayer.php on line 10 Please check: http://wordpress.stackexchange.com/questions/9338/list-category-posts-plugin-upgrade-fails-fatal-error/9340#9340

How to not display the title

You have to add a CSS class to the title with the title_class parameter. Then edit the title_class class in your theme's CSS file. Something like this:

In the post:

[catlist id=3 title_class=lcp_title numberposts=1]

And in your theme's CSS:

.lcp_title{
  display: none;
}

How to insert the shortcode on the theme and not a post or page

<?php echo do_shortcode("[catlist id=3]"); ?>

Please do not ask for support when you are having issues with your CSS. I can't solve every user's CSS problems. Feel free to ask on the forums or WP Answers. But please, read the instructions first.