The reason for my replying to this post was to say that the onus must lay with the engine builder and not the manufacturer of the gasket.
These gaskets are most likely made by "men in sheds" not computerized robots,
so once again check against the old gasket rather than blindly fitting it.
As for the manufacturer telling you that no one else has complained could well have been true as a competent and professional engineer would have checked old against new.
Do you not agree that the engine builder is at least partly to blame?
Roger