DIR-615 is not using any ethernet connection right now, just WIFI.
The provided modem model I'm almost sure is Arris Arris TG2492LG-VTR (the last 3 are the name of the company VTR, so maybe it changes with every company or is just a coincidece), Im 99% sure about it, but right now I'm not in my house anymore to be able to check it.
I really appreceate your help, I'll be checking your answers starting tommorrow at 17:00 (GMT), and from time to time before that with my cel phone if I have time during work. Again thanks a lot for everything.
1) in DIR-615 to set the WAN to static IP (e.g. 192.168.0.250)
2) in the provider modem enable DMZ on IP 192.168.0.250
About those 2 Im gonna try it as soon as I can tomorrow at 17:00, can this be the reason Q3 ARENA is giving me problems to connect too?