Being both Free Scan and ARC do not see the comm port and from all the other data you have collected, I suspect the problem is between WIN 10 and the driver. It seems even though the driver is showing as being installed and working, Win 10 is not able to find and or provide the proper link (path) of the installed hardware of this port when queried by the two programs.
Someone responded to you and stated they have your combination up and running. It would be interesting if that person could send you a copy of the device driver that he is in fact using for you to try. It would also be wise to insure that both of you are running the same beta release of Win 10.
