Файлы для замены:

components/com_k2/css/style.css
components/com_k2/js/k2.js
components/com_k2/models/item.php
components/com_k2/templates/default/item.php
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components/com_k2/css/style.css


найти
.itemRatingList {position:relative;float:left;width:125px;height:25px;overflow:hidden;list-style:none;margin:0;padding:0;background-position:left top;}
заменить на
.itemRatingList {position:relative;float:left;width:250px;height:25px;overflow:hidden;list-style:none;margin:0;padding:0;background-position:left top;}

найти
.itemRatingList a.one-star {width:20%;z-index:6;}
.itemRatingList a.two-stars {width:40%;z-index:5;}
.itemRatingList a.three-stars {width:60%;z-index:4;}
.itemRatingList a.four-stars {width:80%;z-index:3;}
.itemRatingList a.five-stars {width:100%;z-index:2;}
заменить на
.itemRatingList a.one-star {width:10%;z-index:11;}
.itemRatingList a.two-stars {width:20%;z-index:10;}
.itemRatingList a.three-stars {width:30%;z-index:9;}
.itemRatingList a.four-stars {width:40%;z-index:8;}
.itemRatingList a.five-stars {width:50%;z-index:7;}
.itemRatingList a.six-stars {width:60%;z-index:6;}
.itemRatingList a.seven-stars {width:70%;z-index:5;}
.itemRatingList a.eight-stars {width:80%;z-index:4;}
.itemRatingList a.nine-stars {width:90%;z-index:3;}
.itemRatingList a.ten-stars {width:100%;z-index:2;}
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components/com_k2/js/k2.js


найти
$('itemCurrentRating' + itemID).setStyle('width', percentage + "%");
заменить на
$('itemCurrentRating' + itemID).setStyle('width', percentage/2 + "%");
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components/com_k2/models/item.php

line 435
найти
if ( $rate >= 1 && $rate <= 5) {
заменить
if ( $rate >= 1 && $rate <= 10) {

_______________________________________________

components/com_k2/templates/default/item.php

найти:
<li class="itemCurrentRating" id="itemCurrentRating<?php echo $this->item->id; ?>" style="width:<?php echo $this->item->votingPercentage; ?>%;"></li>
<li><a href="#" rel="<?php echo $this->item->id; ?>" title="<?php echo JText::_('1 star out of 10'); ?>" class="one-star">1</a></li>
<li><a href="#" rel="<?php echo $this->item->id; ?>" title="<?php echo JText::_('2 stars out of 10'); ?>" class="two-stars">2</a></li>
<li><a href="#" rel="<?php echo $this->item->id; ?>" title="<?php echo JText::_('3 stars out of 10'); ?>" class="three-stars">3</a></li>
<li><a href="#" rel="<?php echo $this->item->id; ?>" title="<?php echo JText::_('4 stars out of 10'); ?>" class="four-stars">4</a></li>
<li><a href="#" rel="<?php echo $this->item->id; ?>" title="<?php echo JText::_('5 stars out of 10'); ?>" class="five-stars">5</a></li>

заменить на

<li class="itemCurrentRating" id="itemCurrentRating<?php echo $this->item->id; ?>" style="width:<?php echo $this->item->votingPercentage /2; ?>%;"></li>
<li><a href="#" data-id="<?php echo $this->item->id; ?>" title="<?php echo JText::_('K2_1_STAR_OUT_OF_10'); ?>" class="one-star">1</a></li>
<li><a href="#" data-id="<?php echo $this->item->id; ?>" title="<?php echo JText::_('K2_2_STARS_OUT_OF_10'); ?>" class="two-stars">2</a></li>
<li><a href="#" data-id="<?php echo $this->item->id; ?>" title="<?php echo JText::_('K2_2_STARS_OUT_OF_10'); ?>" class="three-stars">3</a></li>
<li><a href="#" data-id="<?php echo $this->item->id; ?>" title="<?php echo JText::_('K2_2_STARS_OUT_OF_10'); ?>" class="four-stars">4</a></li>
<li><a href="#" data-id="<?php echo $this->item->id; ?>" title="<?php echo JText::_('K2_2_STARS_OUT_OF_10'); ?>" class="five-stars">5</a></li>
<li><a href="#" data-id="<?php echo $this->item->id; ?>" title="<?php echo JText::_('K2_2_STARS_OUT_OF_10'); ?>" class="six-stars">6</a></li>
<li><a href="#" data-id="<?php echo $this->item->id; ?>" title="<?php echo JText::_('K2_2_STARS_OUT_OF_10'); ?>" class="seven-stars">7</a></li>
<li><a href="#" data-id="<?php echo $this->item->id; ?>" title="<?php echo JText::_('K2_2_STARS_OUT_OF_10'); ?>" class="eight-stars">8</a></li>
<li><a href="#" data-id="<?php echo $this->item->id; ?>" title="<?php echo JText::_('K2_2_STARS_OUT_OF_10'); ?>" class="nine-stars">9</a></li>
<li><a href="#" data-id="<?php echo $this->item->id; ?>" title="<?php echo JText::_('K2_2_STARS_OUT_OF_10'); ?>" class="ten-stars">10</a></li>