Reproduction steps:
1) Open the attached project
2) Open the scene and Play
3) Check console, "YAY! the dll has been correctly loaded!" should be logged
4) Open Build Settings
5) Uncheck 'Development Build' and 'Script Debugging'
6) Build Windows Standalone into the main project directory (must have the exe next to the TestDll)
7) Run it

Result: Standalone build crashes

Reproduced with: 5.5.0b2, 5.4.0p4, 5.3.6p4, 5.2.5f1