I'm building a website for [a french school][1].

My problem : part of the website content will be private. Me and some other specified users will publish private posts (posts that only the 600 already-registred users will be abble to see).
But an excerpt of those posts (small photo+some text) shall be visible to any visitor in the Home page.
As soon as I set a post category to "Private" (using Role Scopper plugin), all excerpts of this post category, on the Home Page, also stop being displayed.

So what I'm trying to do is : "wheter or not a Post is set to private, force this excerpt to be displayed anyway". Note that I'm not a web dev, I just know a tiny bit of php.

Any plugin / hooks / code to put in the loop or somewhere else ?

Already tried [this solution][2], inserting the code in the index.php loop, but it didn't change anything.

I'm using a theme ([campus theme][3]) that had been largely re-arranged (css-wise).

*EDIT* 
Here is the template code of the homepage:

	<!-- CONTENT -->
		<div class="content <?php echo $layout_class; ?>">
			<div class="content-inner">						
	
			<!-- THE POST LOOP -->  
			<?php while ( have_posts() ) : the_post();?>
				<!-- Page Title -->
				<div class="page-title-breadcrumbs">
					<h1 class="page-title"><span><?php the_title(); ?></span></h1>
						<?php if(get_custom_field('show_breadcrumbs') == 'Yes') : ?>
							<div class="breadcrumbs">| <?php echo get_breadcrumb(); ?></div><?php endif; ?>
					</div>
				<hr class="page-title-hr" />
			
				<!-- Page Caption Section -->
				<?php if(get_custom_field('page_caption') . get_custom_field('page_background_image')) : ?>

					<div class="<?php echo $layout_class; ?>" id="section-page-caption">
						<?php get_template_part( 'includes/element', 'page-caption' ); ?>
					</div >

				<?php endif;?>	

				<!-- THE PAGE CONTENT -->
				<?php the_content(); ?>
						
				<!-- PAGINATION for Multiple pages -->
				<?php wp_link_pages('before=<br /><div id="page-links"><span>Pages:</span>&after=</div><hr />&link_before=<div>&link_after=</div>'); ?>				
				
				<!-- COMMENTS SECTION -->
				
				<?php comments_template(); ?> 
				<div class="hidden"><hr /><?php wp_list_comments('type="comment&avatar_size=64'); ?></div>
				<?php next_comments_link(); previous_comments_link(); ?>
				<div class="hidden"><?php comments_template( '', true ); ?></div>
				<!-- COMMENTS-SECTION -->
				
				
			<?php endwhile; ?>	
			
			</div>
		</div>
		<!-- /CONTENT -->



Thank you for your attention, gentlemen

and sorry if bad english ;)


  [1]: http://www.lfseoul.org/
  [2]: http://wordpress.stackexchange.com/questions/22593/display-public-excerpt-for-private-post
  [3]: http://themeforest.net/item/campus-multipurpose-wordpress-theme/5838533