My website was down for a day after installing Clickdesk. After many go-rounds w/my hosting company, they found that my IP was being blocked by Suhosin, a PHP security feature. Here is the error log:
suhosin: ALERT - script tried to increase memory_limit to 268435456 bytes which is above the allowed value
My hosting company made an exception for this, but I am still evaluating the performance relating to these memory concerns to decide if using the plugin is worth it.
When setting up the Chat Window section, there exists no way to remove a previously uploaded image. In my case, the image I chose blends in with the default ClickDesk background color. It should be as simple as changing the ClickDesk background color, but that option is reserved for paid plans only.