Smart CAT makes two ports for a very simple reason: The lower-numbered one is the one that is made available externally to your software; the other connects to the radio internally, and cannot be used otherwise. And its number is normally the external port plus 100.
Normally when you configure a cat port entry in SmartSDR CAT it only shows the lower port number which you use for a third party program.
The higher number port (com104 in your case) is used to connect to the radio and is normally hidden. To see both port numbers open a cat port for editing and right click in that window. Choose advanced.