You only need to run one copy of screen (i.e. only type the command screen once). From within one instance of screen you can create multiple pages (for want of a better word), which you can then cycle around with ctrl+a [space]
i dont know. but i figured it out how to get it to work:D but, i have one more question. how do i access my mining rig with putty from another ip or computer (my brothers house in this case)? from my house i access ubuntu by typing the LAN adress (10.0.0.3) on putty. what about none local connection?
You need to login to your router and forward port 22, then grab your external ip from something like http://ipchicken.com and use that in putty when your not home.