Freedome settings in router

Freedome states on their support pages:

Port configuration for Freedome on Android, Mac and Windows

In some cases, for example on your home network, you may have to configure and set up port access in order to connect to Freedome.

Our Android, Windows and Mac OS X products use the OpenVPN protocol.

The ports for Android, Mac and Windows are:

    TCP/UDP ports in the range 2740 - 2749

    TCP port 443

Is it fine ... and secure ... to only use one of the two?  For example, if your router allows TCP/UDP and a range, you don't have to enter "TCP port 443" to open up that port?  Or, do both need to be enabled within the router port forwarding?  Also, both "Internal" and "External" ports?  Do you have to reboot the router for these settings to take effect?

When you only set up a router every few years, it is not easy to remember all the steps.

TIA!