Same here; winwin_create returns undefined. I tried to test the demo in IDE v2024.4.1.152, Runtime v2024.4.1.201. This in Output seems to be the problem. I didn’t change anything in the demo btw.
LoadLibraryW("C:\Users\lsk21\AppData\Local\GameMakerStudio2\GMS2TEMP\winwin-demo_399161E_VM\winwin_x64.dll") failed with error code 87 ("The parameter is incorrect.")