Nie potrafię sobie poradzić z problemem, który polega na ograniczeniu wyświetlania ilości miniatur (thumbs) do pierwszych 3 np.
Kod pluginu:

[PHP] pobierz, plaintext 
<?php
/**
 * @version		3.0.1
 * @package		Simple Image Gallery (plugin)
 * @author		JoomlaWorks - <a href="http://www.joomlaworks.net" target="_blank">http://www.joomlaworks.net</a>
 * @copyright	Copyright (c) 2006 - 2014 JoomlaWorks Ltd. All rights reserved.
 * @license		GNU/GPL license: <a href="http://www.gnu.org/copyleft/gpl.html" target="_blank">http://www.gnu.org/copyleft/gpl.html</a>
 */
 
// no direct access
defined('_JEXEC') or die('Restricted access');
 
class SimpleImageGalleryHelper {
 
	public static function renderGallery($srcimgfolder, $thb_width, $thb_height, $smartResize, $jpg_quality, $cache_expire_time, $gal_id)
	{
 
		// API
		jimport('joomla.filesystem.folder');
 
		// Path assignment
		$sitePath = JPATH_SITE.'/';
		if(JRequest::getCmd('format')=='feed')
		{
			$siteUrl = JURI::root(true).'';
		}
		else
		{
			$siteUrl = JURI::root(true).'/';
		}
 
		// Internal parameters
		$prefix = "jw_sig_cache_";
 
		// Set the cache folder
		$cacheFolderPath = JPATH_SITE.DS.'cache'.DS.'jw_sig';
		if (file_exists($cacheFolderPath) && is_dir($cacheFolderPath))
		{
			// all OK
		}
		else
		{
			mkdir($cacheFolderPath);
		}
 
		// Check if the source folder exists and read it
		$srcFolder = JFolder::files($sitePath.$srcimgfolder);
 
		// Proceed if the folder is OK or fail silently
		if (!$srcFolder)
			return;
 
		// Loop through the source folder for images
		$fileTypes = array('jpg', 'jpeg', 'gif', 'png');
		// Create an array of file types
		$found = array();
		// Create an array for matching files
		foreach ($srcFolder as $srcImage)
		{
			$fileInfo = pathinfo($srcImage);
			if (array_key_exists('extension', $fileInfo) && in_array(strtolower($fileInfo['extension']), $fileTypes))
			{
				$found[] = $srcImage;
			}
		}
 
		// Bail out if there are no images found
		if (count($found) == 0)
			return;
 
		// Sort array
		sort($found);
 
		// Initiate array to hold gallery
		$gallery = array();
 
		// Loop through the image file list
		foreach ($found as $key => $filename)
		{
 
			// Determine thumb image filename
			if (strtolower(substr($filename, -4, 4)) == 'jpeg')
			{
				$thumbfilename = substr($filename, 0, -4).'jpg';
			}
			elseif (strtolower(substr($filename, -3, 3)) == 'gif' || strtolower(substr($filename, -3, 3)) == 'png' || strtolower(substr($filename, -3, 3)) == 'jpg')
			{
				$thumbfilename = substr($filename, 0, -3).'jpg';
			}
 
			// Object to hold each image elements
			$gallery[$key] = new JObject;
 
			// Assign source image and path to a variable
			$original = $sitePath.str_replace('/', DS, $srcimgfolder).DS.$filename;
 
			// Check if thumb image exists already
			$thumbimage = $cacheFolderPath.DS.$prefix.$gal_id.'_'.strtolower(self::cleanThumbName($thumbfilename));
 
			if (file_exists($thumbimage) && is_readable($thumbimage) && (filemtime($thumbimage) + $cache_expire_time) > time())
			{
				// do nothing
			}
			else
			{
				// Otherwise create the thumb image
 
				// begin by getting the details of the original
				list($width, $height, $type) = getimagesize($original);
 
				// create an image resource for the original
				switch($type)
				{
					case 1 :
						$source = @ imagecreatefromgif($original);
						if (!$source)
						{
							JError::raiseNotice('', JText::_('JW_PLG_SIG_ERROR_GIFS'));
							return;
						}
						break;
					case 2 :
						$source = imagecreatefromjpeg($original);
						break;
					case 3 :
						$source = imagecreatefrompng($original);
						break;
					default :
						$source = NULL;
				}
 
				// Bail out if the image resource is not OK
				if (!$source)
				{
					JError::raiseNotice('', JText::_('JW_PLG_SIG_ERROR_SRC_IMGS'));
					return;
				}
 
				// calculate thumbnails
				$thumbnail = self::thumbDimCalc($width, $height, $thb_width, $thb_height, $smartResize);
 
				$thumb_width = $thumbnail['width'];
				$thumb_height = $thumbnail['height'];
 
				// create an image resource for the thumbnail
				$thumb = imagecreatetruecolor($thumb_width, $thumb_height);
 
				// create the resized copy
				imagecopyresampled($thumb, $source, 0, 0, 0, 0, $thumb_width, $thumb_height, $width, $height);
 
				// convert and save all thumbs to .jpg
				$success = imagejpeg($thumb, $thumbimage, $jpg_quality);
 
				// Bail out if there is a problem in the GD conversion
				if (!$success)
					return;
 
				// remove the image resources from memory
				imagedestroy($source);
				imagedestroy($thumb);
 
			}
 
			// Assemble the image elements
			$gallery[$key]->filename = $filename;
			$gallery[$key]->sourceImageFilePath = $siteUrl.$srcimgfolder.'/'.self::replaceWhiteSpace($filename);
			$gallery[$key]->thumbImageFilePath = $siteUrl.'cache/jw_sig/'.$prefix.$gal_id.'_'.strtolower(self::cleanThumbName($thumbfilename));
			$gallery[$key]->width = $thb_width;
			$gallery[$key]->height = $thb_height;
 
		}// foreach loop
 
		// OUTPUT
		return $gallery;
 
	}
 
 
 
	/* ------------------ Helper Functions ------------------ */
 
	// Calculate thumbnail dimensions
	public static function thumbDimCalc($width, $height, $thb_width, $thb_height, $smartResize)
	{
 
		if ($smartResize)
		{
 
			// thumb ratio bigger that container ratio
			if ($width / $height > $thb_width / $thb_height)
			{
				// wide containers
				if ($thb_width >= $thb_height)
				{
					// wide thumbs
					if ($width > $height)
					{
						$thumb_width = $thb_height * $width / $height;
						$thumb_height = $thb_height;
					}
					// high thumbs
					else
					{
						$thumb_width = $thb_height * $width / $height;
						$thumb_height = $thb_height;
					}
					// high containers
				}
				else
				{
					// wide thumbs
					if ($width > $height)
					{
						$thumb_width = $thb_height * $width / $height;
						$thumb_height = $thb_height;
					}
					// high thumbs
					else
					{
						$thumb_width = $thb_height * $width / $height;
						$thumb_height = $thb_height;
					}
				}
			}
			else
			{
				// wide containers
				if ($thb_width >= $thb_height)
				{
					// wide thumbs
					if ($width > $height)
					{
						$thumb_width = $thb_width;
						$thumb_height = $thb_width * $height / $width;
					}
					// high thumbs
					else
					{
						$thumb_width = $thb_width;
						$thumb_height = $thb_width * $height / $width;
					}
					// high containers
				}
				else
				{
					// wide thumbs
					if ($width > $height)
					{
						$thumb_width = $thb_height * $width / $height;
						$thumb_height = $thb_height;
					}
					// high thumbs
					else
					{
						$thumb_width = $thb_width;
						$thumb_height = $thb_width * $height / $width;
					}
				}
			}
 
		}
		else
		{
 
			if ($width > $height)
			{
				$thumb_width = $thb_width;
				$thumb_height = $thb_width * $height / $width;
			}
			elseif ($width < $height)
			{
				$thumb_width = $thb_height * $width / $height;
				$thumb_height = $thb_height;
			}
			else
			{
				$thumb_width = $thb_width;
				$thumb_height = $thb_height;
			}
 
		}
 
		$thumbnail = array();
		$thumbnail['width'] = round($thumb_width);
		$thumbnail['height'] = round($thumb_height);
 
		return $thumbnail;
 
	}
 
	// Path overrides
	public static function getTemplatePath($pluginName, $file, $tmpl)
	{
 
		$mainframe = JFactory::getApplication();
		$p = new JObject;
		$pluginGroup = 'content';
 
		$jTemplate = $mainframe->getTemplate();
 
		if($mainframe->isAdmin()){
			$db = JFactory::getDBO();
			if (version_compare(JVERSION, '1.6', 'ge'))
			{
				$query = "SELECT template FROM #__template_styles WHERE client_id = 0 AND home = 1";
			}
			else
			{
				$query = "SELECT template FROM #__templates_menu WHERE client_id = 0 AND menuid = 0";
			}
			$db->setQuery($query);
			$jTemplate = $db->loadResult();
		}
 
		if (file_exists(JPATH_SITE.DS.'templates'.DS.$jTemplate.DS.'html'.DS.$pluginName.DS.$tmpl.DS.str_replace('/', DS, $file)))
		{
			$p->file = JPATH_SITE.DS.'templates'.DS.$jTemplate.DS.'html'.DS.$pluginName.DS.$tmpl.DS.$file;
			$p->http = JURI::root(true)."/templates/".$jTemplate."/html/{$pluginName}/{$tmpl}/{$file}";
		}
		else
		{
			if (version_compare(JVERSION, '1.6.0', 'ge'))
			{
				// Joomla! 1.6+
				$p->file = JPATH_SITE.DS.'plugins'.DS.$pluginGroup.DS.$pluginName.DS.$pluginName.DS.'tmpl'.DS.$tmpl.DS.$file;
				$p->http = JURI::root(true)."/plugins/{$pluginGroup}/{$pluginName}/{$pluginName}/tmpl/{$tmpl}/{$file}";
			}
			else
			{
				// Joomla! 1.5
				$p->file = JPATH_SITE.DS.'plugins'.DS.$pluginGroup.DS.$pluginName.DS.'tmpl'.DS.$tmpl.DS.$file;
				$p->http = JURI::root(true)."/plugins/{$pluginGroup}/{$pluginName}/tmpl/{$tmpl}/{$file}";
			}
		}
		return $p;
	}
 
	// Replace white space
	public static function replaceWhiteSpace($text_to_parse)
	{
		$source_html = array(" ");
		$replacement_html = array("%20");
		return str_replace($source_html, $replacement_html, $text_to_parse);
	}
 
	// Cleanup thumbnail filenames
	public static function cleanThumbName($text_to_parse)
	{
		$source_html = array(' ', ',');
		$replacement_html = array('_', '_');
		return str_replace($source_html, $replacement_html, $text_to_parse);
	}
 
} // End class
[PHP] pobierz, plaintext 

Może taka zmiana pomoże (nie mam jak sprawdzić):

Po linii 57 dodać:

[PHP] pobierz, plaintext 
$limit =3;
[PHP] pobierz, plaintext 

Po linii 64 (po found[]) dodać:

[PHP] pobierz, plaintext 
 if(count($found)>=$limit) break;
[PHP] pobierz, plaintext 

I jeszcze link całym kodem + te linijki które dodałem są podświetlone na zielono: https://www.diffchecker.com/0l1x5snp

Pozdrawiam