Because grc said "stealth" on port 80 that means that it is 100% for certain that your ISP is blocking port 80
As for accessing your web control panel from outside on port 82. I REALLY really do NOT recommend having the web control panel visible from outside. That is a huge security risk that should not be opened. If you really need to use the control panel from outside then I recommend using PuTTy to use a secure port through the SSH server for access to the internal web control panel. But to answer your question directly you would run the "setup" and enable the control panel in "y" mode and the just use <a href='http://your-url:82/' target='_blank'>http://your-url:82/</a> to access to control panel. But again I do not recommend doing that because it would grant "root" access to your router and your internal network if the password was hacked.
