Thanks James for the feedback and trying ScriptBasic.
The sb-dev-msvc repo uses the ScriptBasic build system that creates .h include files and documentation from the C source. AIR (co-maintainer that has moved on) created a standalone Microsoft Visual C and Strawberry Perl compiler tailored for the ScriptBasic build system. The build system generates both Windows 64 bit and Linux 64 bit versions.
The sb-dev-win32 repo contains a pre-built Windows 32 bit version of ScriptBasic as an installer. It was compiled with TDM-GCC-32 and uses static .h files. The 32 bit version of ScriptBasic offers extensions that the 64 bit version doesn't support. COM / VB6 OCX support and the OxygenBasic DLLC (FFI, structures and string type conversions) extensions make the 32 bit version a good place to start.