A simple shortcode that will return either the current users or a given users rank progress using Visual Composers Progress Bar.

Rank Progress Shortcode

/**
 * Users Rank Progress
 * This shortcode will render the users current rank progress using the Visual Composer Progress Bar shortcode.
 * Shows either the current users rank progress or a given user ids. Returns the content if user is not logged in.
 * Requries myCRED 1.4
 * @version 1.1
 */
add_shortcode( 'mycred_rank_progress', 'mycred_pro_users_rank_progress' );
function mycred_pro_users_rank_progress( $atts, $content = NULL ) {
	// Make sure we are logged in
	if ( ! is_user_logged_in() ) return $content;

	// Make sure myCRED is installed!
	if ( ! function_exists( 'mycred' ) ) return '';

	extract( shortcode_atts( array(
		'user_id' => get_current_user_id()
	) ) );

        // Load myCRED
        $mycred = mycred();
 
        // Ranks are based on a total
        if ( $mycred->rank['base'] == 'total' )
                $key = $mycred->get_cred_id() . '_total';
        // Ranks are based on current balance
        else
                $key = $mycred->get_cred_id();
 
        // Get Balance
        $users_balance = $mycred->get_users_cred( $user_id, $key );
       
        // Rank Progress
       
        // Get the users current rank post ID
        $users_rank = (int) mycred_get_users_rank( $user_id, 'ID' );
       
        // Get the ranks set max
        $max = get_post_meta( $users_rank, 'mycred_rank_max', true );
       
        // Calculate progress. We need a percentage with 1 decimal
        $progress = number_format( ( ( $users_balance / $max ) * 100 ), 1 );
       
        // Visual Composer customization
        $options = '';
       
        // If progress is less then 100%, use the stipped animation to indicate progress
        if ( $progress < number_format( 100, 1 ) )
                $options = 'options="striped,animated"';
        // Else use the fixed background color to indicate completion
        else
                $progress = number_format( 100, 1 );

	ob_start();
?>
 
<div class="bp-widget mycred-field">
        <div class="wpb_row row">
                <div class="col-md-12 col-sm-12 wpb_column column_container">
                        <div class="wpb_wrapper">
                                <div class="vc_text_separator wpb_content_element separator_align_left"><div>Rank Progress</div></div>
                        </div>
                </div>
        </div>
        <?php echo do_shortcode( '[vc_row][vc_column width="1/1"][vc_progress_bar values="' . $progress . '|' . get_the_title( $users_rank ) . '" bgcolor="custom" ' . $options . ' custombgcolor="#E74C3C" title="" units="%"]<p><span class="description">your current progress towards the next rank</p>[/vc_column][/vc_row]' ); ?>
 
</div>
<?php
	$content = ob_get_contents();
	ob_end_clean();

	return $content;
}

As of 1.7, this seems to be broken. It divides by zero on line 42

Change line 36 to this:
$users_rank = (int) mycred_get_users_rank_id( $user_id, $type_id );