I had a similar problem with a php include. The form included appeared at the top of the $content rather than where the shortcode was in the text. I changed the code to this:
ob_start();
include 'include-file.php';
$content = ob_get_clean();
return $content;
However this might not be the problem with your plugin shortcode. It’s just what worked for me.
in what file did you make that change?
I changed it in the functions.php files because that’s where the shortcode function I was using was located. However if the problem is with a plugin the file that you’ll need to look at will be within the plugin.
I should point out that this might not be able to solve your problem. I’ll try to have a look at the code for the plugin later and see if I can see where the problem lies.
I decided to just create a new homepage template and put the section i need at the top above where the editor content resides.
This is just a work-around but…
Out of interest are you still using the plugin? Have you used this code to display the slider:
<?php include (ABSPATH . '/wp-content/plugins/wp-featured-content-slider/content-slider.php');?>
i’m using the shortcode because its within the page editor.