ZD1200 with a Proxy Server

unknown

I have a ZD1200 with 6 R500 AP's connected. The Wi-Fi is working fine insofar as a browser can be reconfigured to the proxy settings and off it goes. Where I have the issue is that the WPAD.DAT file does not seem to influence the controller and how it finds the internet for .SPT file application. I have downloaded the file to my laptop and applied it to the controller but the process fails every time. Has anyone else had this issue and get a workaround? Or, is it that we have to remove the controller from the network to apply the SPT file and return it?