Reference guide for workflow?

Is there a reference guide for workflow studio?
The Workflow Studio manual provides a good overview of how to configure, use and programmatically run workflow studio. However there doesn't seem to be a reference manual that details things such as:
- Class hierarchy and public properties & methods, including what is available programmatically and what is exposed to the workflow diagram script blocks
- Inbuilt functions/constants/variables available to the workflow diagram script blocks

Unfortunately there is no such info, the only documentation for now is the user manual. 

As for the scripter, you have two context variables declared: _Workflow, which provides you with the TWorkflowDiagram object associated with the current workflow instance, and _Task, which provides you a TTaskInstance object associated with the task (if any).