Hiding Flex Slider completely when no image

Hi there, I am using your module – Flex Slider – which I downloaded from this page. http://wp-types.com/home/module-manager/

This module is being used on single pages which contain a Review (which is a Child Post of Main Listing) and an image which has a custom post type of Slides (which is also a Child Post of Main Listing).

Anyway, on the Single page, an image (Slide) is optional so what I would like is to display the FlexSlider conditionally. I tried the WhatIf conditional statements but in this case they are not working:

[wpv-if f1="wpcf-slide-image" evaluate="!empty($f1)"]

[/wpv-if]

Any idea how I can hide the slider – including the Divs?

Cheers