Phew, it took me a while to find the twonkymedia-server.ini on my server, because it's not in the /etc (which is where - as far as I know about Linux - it should be located)
However, now I found it, edited it according to that post of your's but it still doesn't work.
Before I start posting config files etc. I have 2 questions:
1) which port would you recommend when 80 is in use? I took 76 which is the closest not-well-known one. Ok?
2) I don't find anything in the setup guide where I adjust for example user credentials. Yes, I don't need a VPN, but without VPN, is my stream really available for ANYbody connecting to me IP/port?? I can't believe this. Furthermore, the "PlugPlayer" which is AFAIK the most popular player for this kind of setup also asks for credentials and doesn't even allow to complete the setup without that.