I've seen that when you click on a folder to view the contents of that folder and then click the up arrow to go back a folder, it adds "../" to $this->cur_path.

So say you first browse: /home/images
and you click on the folder buttons so now you are in /home/images/buttons
You click on the up arrow to go back to /home/images but $this->cur_path now displays as /home/images/buttons/../

Thats true partialy....
Initialy $this->cur_path is /home/images/buttons/../ but in function load_cur_dir_info it is done
$this->cur_path = str_replace('\\','/', realpath($this->cur_path)).'/';
and it is converted to /home/images/

Is there a chance that you have the initial version of the class?

And thank you for the possitive comments