Use and understanding
Configuration and internationalisation
Error codes and constants
Up to date definitive reference.
How to use the test environment
General overview of test environment
2008 era written specifications
These were the original master documents and are now showing their age.
Originals. Becomming obsolete
Original master document
Especially important for interfacing with legacy data.
Specification of inputs
Allowed and special input formats.
Miscellaneous odd bits