Optional Sub Directory Problem

I’m trying out File Away for the first time, trying to get a shortcode entry working right. I can do a “Directory View” of one of my directories just fine, however, whenever I try and populate the “Optional Sub Directory” field to get it to auto display a sub folder instead of the main directory, it doesn’t work. If I check Apache logs I get this:

[Fri Jul 20 15:55:27.093897 2018] [php7:warn] [pid 3656] [client x.x.x.x:56650] PHP Warning: count(): Parameter must be an array or an object that implements Countable in /var/www/html/wp-content/plugins/file-away/lib/cls/class.fileaway.php on line 68, referer: https://testsite/index.php/training/training-videos/?drawer=training-content

I tried searching for this particular error and didn’t come up with much. Any guidance would be much appreciated. Thanks!