This is just a visual experiment, it has no intention to be used as a service. It is live because it is pulling live data from the TfL prediction summary API, which returns approximate arrival times for the next 30 minutes. The default simulation speed is 5 and it can be adjusted to 1 for an experience as 'live' as http://traintimes.org.uk/map/tube/
As for the Circle line, it is just commented out in the code because it wasn't really adding anything. The prediction summary doesn't return isolated data for the Circle (at least it didn't when I made this experiment) so I had to improvise by merging District, H&C and Metropolitan. It was an approximation of the approximation. It wasn't looking great, so I just left it out.