The Vectorworks 2019 SDK requires Visual Studio 2017 (toolset v141) on Windows and Xcode version 8.2 on the Mac.
Vectorworks 2018 has been converted to Unicode using UTF-16 internally. The SDK's TXString class has been converted.
The Dialog Builder tool, used to design Layouts for Script and SDK, is still built-in. Dialog_Builder
Developer tools under the 'Debug' menu are available after running the following VectorScript (make a new script in the Resource Manager and run it):
EnableDebugMenu;Running this script will restart Vectorworks and then a Debug menu will be available.