Finally found a solution,
if someone got the same issue, the author of the add-on seems to don’t want to update the add-on to work with ACF4.
But there is a fork downloadable here that work with ACF4.
				
		
	 
	
	
		
	
		
	
		
		
	
	
		
		
			
		
	
	
		
		
		 @elliot by wp-plugins did you mean wp-content/plugins ? If then.. yes
I also try to include it in my theme, but after some debug tests, its seems that the plugin is fire before ACF set up. class_exists( 'acf_Field' ) return false.
I send an issue to the developper of the add-on.
Thank you.