Understanding a train schedule should be reasonably straightforward. Call points are split into rows and each row has information about the call point.
At the very top is the service summary and latest report if running.
Top left is most notably the location. Depending on the size of the screen, either to the right of it (or below it) will be the platform and line, and any information about the stop (if ailable).
Platforms
A booked platform is clickable and will take you to the location page with immediate filter of the same platform. Some platforms will not be clickable. Platforms collected from other sources (which would otherwise be missing from the timetable) are not clickable. Nor are "actual" platforms, coloured green or red, with the platform the train actually used.
Timings
The middle column, present whether or not a train is running, are the booked times. a. indicative of arrival time, d. departure and p. pass.
The rightmost column may or may not be filled and will only show stuff if the train is running.
Green indicates an on-time report give or take 30 seconds. Red indicates late, and orange indicates early. An asterisked * report is an assumption based on signal movement data, where otherwise there would be no report.
A "NR" means no report, and the train hasn't given an actual time, such as in poor signalling areas or if the train is off-route.