Hello Monsieur Gustav,
I understand that, although it would be better to be able to change the port during runtime.
The main ideia was just to have access to the listening port inside the blueprint and to be able to specify several different ports even if it is not in runtime.
Maybe I can give my contribution later in this subject.
Another issue that I have noticed was some problems with Openframeworks.
I have tested your plugin with OSCulator and everything seems to works well, but when I send messages from Openframeworks, the plugin does not respond.
Made another test sending from OF to OSCulator routing the message to Unreal plugin and it works.
The problem seems to be the support of bundles. I had the same issues with OSC and Unity.
I´ll search more about this subject and report it later.