Wordpress help - How to apply filters in custom fields?

[Viruthagiri]

I'm using cubepoints. It has a module named "paid content". Paid content

module hides the post content. User need to pay "X" points to view the

page. But this module only hides main content. I mean it hides the content

whatever "the_content" loop calls.

Here is my problem. I'm using magic fields plugin. It is a plugin to create

custom fields.
So my site doesn't use the_content loop.

For example this is the code my theme uses instead of the_content loop.

if (function_exists('get_field')) { 
                        $requirements = get_field

('requirements_requirements');
                            if($requirements){  
                                foreach($requirements as $requirement){
                                echo $requirement;
                                } 
                            } 
                        }

Now i want to hide these custom field contents.
This is the full source code of paid content module.

http://pastebin.com/MqgdJj6m

The filter function code is from line 187 to line 204 (see the code below).

function cp_module_pcontent_post_content($content){
    		global $post;
    		global $cp_module_pcontent_hide;
    		if(!in_array($post->ID,(array)$cp_module_pcontent_hide)){
    			return $content;
    		}
    		$c = '<p>' . get_option('cp_module_pcontent_text_pay') . 

'</p>';
    		$c .= apply_filters('cp_module_pcontent_post_content_'.

$post->ID, '');
    		$c .= '<form method="post">';
    		$c .= '<input type="hidden" name="cp_module_pcontent_pay" 

value="'.$post->ID.'" />';
    		$c .= '<p><input type="submit" value="'.get_option

('cp_module_pcontent_text_button').'" /></p>';
    		$c .= '</form>';
    		if(!is_user_logged_in()){
    			$c = get_option('cp_module_pcontent_text_logout');
    		}
    		$c = str_replace('%points%',cp_formatPoints(get_post_meta

($post->ID,'cp_pcontent_points', 1)),$c);
    		return $c;
    	}

So can anyone alter the code to hide the custom fields?
Thanks