Sorry, I could not find this line in the admin_cms/contents_insert.php page.
The one that is closest is
<input type="text" name="ContentRefID" id="ContentRefID" value="<?php echo((isset($_POST['ContentRefID']))?$_POST['ContentRefID']:"") ?>" class="validate['required','alphanum']" />
which i changed to
<input type="text" name="ContentRefID" id="ContentRefID" value="<?php echo((isset($_POST['ContentRefID']))?$_POST['ContentRefID']:"") ?>" class="validate['required']" />
The change made no difference.
I'm attaching a copy of my admin_cms/contents_insert.php file
Regards
Rune