Help & troubleshooting for channels on your Roku device, including adding/removing channels, logging in to, authenticating, or activating a channel, channel-specific playback issues, assistance contacting channel publishers to report issues, and adjusting channel-specific settings.
Re: http://go.roku.com/channelsignup is incorrectly redirecting to https://www.roku.com/legal
You'll want to review the URL that is displayed on screen inside that channel when trying to authenticate the channel with your TV provider from inside the channel's own settings, and use that web address. That doesn't appear to be the correct URL.
Thanks for letting us know about the other website issue though, we'll share this feedback with the team.