It would be very nice if you could make all config values available as commandline parameters. For "port" it is already done but minidlna still needs a config file. If minidlna would run without a config but with commandline parameters it would be possible to configure it on-the-fly.
This would enable features like a KDE action "share current directory". It should not be that hard to implement and I would ask you kindly to add this functionality.
Would be nice if you could think about the idea and perhaps I can start sharing a folder with one click in future.
Keep up the great work and if you have any questions let me know.