@yourfriendkarol
Basically what I did was ;
Load --> Site with proxy list
Click on the IP and use the "Get Element Text" and do the same for "IP" (save both with useful name like IP & port)
Now hit "proxy for browser" and use the @ varations IP and type : and then again for port.
If its a bit unclear let me know and i'll guide you tomorrow, but I have to catch some sleep now :)