Hey Dave,
The current definitive source for function workings, etc. is the TurboActivate.h file. We plan on adding a web resource for all the functions later this year.
Each language also has function comments for each of the functions that explains what actually happens. So, what you're using:
ta.IsGenuineEx(90, 14, true);
That means re-verify with the servers every 90 days with a 14 day grace period if there are internet error, and if the user initially activated offline then skip the re-verification with the servers.
Does that make sense?