The "What's New" Developer's guide links to the Appeon Product Manuals Website at:
The "Getting Started" book lists the books included in the documentation set, but not all of them are available at the link above.
- User's Guide
- Deploying Components as .NET Assemblies or Web Services
- PowerScript® Reference
- DataWindow Reference
- Objects and Controls
In addition, some that are present are misnamed in the online Library:
- PowerBuilder Native Interface (PBNI) Programmer’s Guide and Reference (named simply "Programmers Guide")
- Connection Reference (named "Database Parameters")
- PowerBuilder Extension Reference (named "PowerBuilder Extensions")
I was specifically looking for documentation on Enhanced ORCAScript, which the "What's New" says is documented in the "User's Guide".