Minecraft port forwarding

I’ve been trying to fix it for hours and am thinking about giving it up for the night, but wanted to post to get some advice. I want to setup single port forward just on Minecraft port 25565 for my Minecraft server.

I have Linksys WRT54GL router and some powerline adapters. Then everything is hooked up to my PC.

I’ve tried enabling DMZ but that didn’t work for some reason so I set up just one port instead. I have dynamic IP allocated by DHCP but I double checked and I forwarded the right IP, tho I do know it would be better to use static IP for Minecraft servers.

I’m pretty sure my router and everything is ok, the only thing I’m struggling with is how to open ports on my router so that they’re accessible from outside world.