I dunno, those look quite realistic and even a good thing for a plugin system that needs to run in a sandbox:

- The Windows API is not supported => would be a security nightmare if allowed

- C++ exceptions are not supported => not surprising, game code usually forbids exceptions anyway, along with RTTI

- C++ threads are not supported => really shouldn't be needed in a plugin system,

- The GDI+ wrapper is very incomplete => surprising that they even attempt to wrap GDI+

- The WebAssembly module must be compiled in Debug mode for C/C++ code for symbols to be visible while debugging => need to compile in debug mode in order to debug, doh.