Can you change the COM port being used by Realport?

I recently installed a Digi One SP device and am using it in RealPort mode. But, I have an old app from yesteryear that is hard-coded and requires me to use serial COM1. I tried to change the COM assigned to the device in the ‘Device Manager>Ports(COM & LPT)>Digi ONe SP - Port 1>Properties>Port Settings’ tab, but the ‘Advanced…’ button is not available to change the COM# being used.
I verified that COM1 is available and currently unassigned. I even uninstalled the driver and reinstalled. It just goes back to COM2. I have logged into the Web Server for the device thinking it may be able to be changed there, but it is not. You can only change the description there.
I am out of ideas. Has anyone found a way to change the COM# being used by RealPort?