To modify real port settings you must call configuration manager. It could be opened in several ways:
1. Click "Edit" menu option and select "Real serial port settings"
2. Right-click necessary real port icon in a Ports Bundle Tree and select "Real serial port settings" option

3. Press "Ctrl" + "R"
Real serial port settings manager will be opened in a new window:

You have an option to either match remote port settings or set custom ones.
If you select "Match the opening settings of the other end's main port" option make sure you have set remote as main port. This option could be useful if you want to open real serial port with exactly the same settings as virtual (splitted) one.
As an alternative, you may choose "Use custom settings" option which allows you to set different values such as:
Possible values are: 110, 300, 600, 1200, 2400, 4800, 9600, 14400, 19200, 38400, 56000, 57600, 115200, 128000 and 256000 bauds. By default 110 is selected.
Possible values are: "No parity", "Odd", "Even", "Mark" and "Space". Default value is "No parity".
Possible values are: 5, 6, 7 and 8. By default "7" is selected.
Possible values are: "1 stop bit" and "2 stop bits". Default value is "1 stop bit".
Possible values are: "None", "Hardware", "Xon/Xoff". Default value is "None".