Why is JW Player not working in custom Content Type?
There are many ways you can do this 


Jwplayer Drupal Module


Video : http://www.youtube.com/watch?v=mAAIfi0pYHw


Embedding jwplayer in HTML5


http://www.longtailvideo.com/support/jw-player/28839/embedding-the-player/

For your example :

WRONG CODE (dont use)
    

&lt;div class="field-item even"&gt;

&lt;span class="file"&gt;

&lt;img class="file-icon" alt="" title="video/mp4" src="/0065bd-doc/ops-lop/modules/file/icons/video-x-generic.png"&gt; 

&lt;a href="/page24_3.mp4" type="video/mp4; length=4838313"&gt;page24.mp4&lt;/a&gt;

&lt;/span&gt;&lt;/div&gt;&lt;/div&gt;


Try This 

&lt;div class="field-items"&gt;

    &lt;div class="field-item even"&gt;
        &lt;span class="file"&gt;

            &lt;img class="file-icon" alt="" title="video/mp4" src="/0065bd-doc/ops-lop/modules/file/icons/video-x-generic.png"&gt; 

            &lt;div id='playerNrEyADwjFyrz' onclick='jwVideoSetup('/page24_3.mp4')'&gt;&lt;/div&gt;
            &lt;script type='text/javascript'&gt;
                function jwVideoSetup(src)
                {
                    jwplayer('playerNrEyADwjFyrz').setup({
                       file: src,
                       title: 'video title',
                       width: '100%',
                       aspectratio: '16:9'
                    });
                }
            &lt;/script&gt;

        &lt;/span&gt;
    &lt;/div&gt;
&lt;/div&gt;