Featured Pages Icons

If you add this to your child-theme functions php:

add_filter('fp_img_src', 'my_custom_fp_imgs', 10, 2);
function my_custom_fp_imgs( $original_image, $fp_single_id){
    $custom_img = array(
        //fp_id (one, two,three) => image_src
        'two' => 'wp-content/uploads/2014/05/49677d1c84277_big.jpg',
        'three' => 'wp-content/uploads/2014/05/49677d1c84257_big.jpg',
    );
    if ( array_key_exists($fp_single_id, $custom_img) )
        return sprintf('<img class="attachment-tc-thumb" width="270" height="250" alt="fp-image-%1$s" src="%2$s">',
                    $fp_single_id,
                    $custom_img[$fp_single_id]
               );
    return $original_image;
}

And replacing those img_src with your image (270×250 size) urls you can do that.
But I think you might want to change the titles too, so:

add_filter('tc_fp_title' , 'my_custom_fp_titles', 10 , 2);
function my_custom_fp_titles( $original_title , $fp_single_id) {

    //assigns a custom title by fp_id
    $custom_title = array(
        //fp id => 'Custom title'
        'two' => 'My custom title1',
        'three' => 'My custom title2'
    );

    if ( array_key_exists($fp_single_id, $custom_title) )
        return $custom_title[$fp_single_id];

    //if no custom title is defined for the current page id, return original
    return $original_title;
}