We like the idea that you suggest. Previously it was retaining image name but on simple names like “image.jpg” it was checking too many names if they exist then it would suggest other name by increasing integer at the end like “image-18.jpg” .
This was problem with browser caching for example if image deleted from server but exists on users’ browser cache then it will show old image instead of new one.
In short you can disable image name randomization by changing following line in upload() model in /sys/app/models/Adpics.php file
$upload_config['encrypt_name'] = true;
$upload_config['encrypt_name'] = false;
Try it and let us know if it works for you.
Also we will look for better solution for this and add it to next release if we find one.