FCEUX 2.6.5 and FCEUX 2.6.6 do not work

[Kulkoba]

The 2.6.5 and 2.6.6 versions of the FCEUX core do not work.
When the core is chosen there is sound but there is no image and all we can see is a flat-grey screen.
Mac OS 15.1.1 and OpenEmu 2.4.1
When the core file is replaced by some older version it works. But as soon as OpenEmu is restarted and it connects to the repository the version is updated to the latest and it doesn't work again.
Were these versions tested? Can they be fixed or at least temporarily removed from the repository, until there's a fix?
Thanks