Zhiyi Zhang (@zhiyi) commented about dlls/ntdll/actctx.c:
if (RtlGetVersion(&rovi) == ERROR_SUCCESS){TRACE("windows version: win %ld, build %ld\n", rovi.dwMajorVersion, rovi.dwBuildNumber);}else{ERR("RtlGetVersion failed\n");rovi.dwMajorVersion = 0;rovi.dwBuildNumber = 0;}- }
 - return rovi.dwMajorVersion >= 10 && rovi.dwBuildNumber >= 14393;
 +}
+NTSTATUS query_dword_option( HANDLE hkey, LPCWSTR name, LONG *value );
Put this in ntdll_misc.h.