In his case I think the rawinputhook.exe is trying to send OK to skip the disclaimer screens. I'm not sure that's gonna work for his build though... Disabling that feature just tells GameEx not to send these commands to MAME, and in the instance he uses a custom compile that isn't needed anyways. But yes, a log would have been helpful... He left me with the impression that he wants to change the default bezel, not that he's having issues launching games on account of it.