How do I turn off the defense grid?

Worth a try if the mod is in use. But NRaas Overwatch helps resolve an issue with with the meteor shower alarms getting stuck across the three types of future worlds beginning with version 111, I wasn't aware that it prevents the showers from happening entirely. The current OW version is 122 so these reports are from quite a while ago, probably very soon after ITF was released as v111 was Twallan's last release and not that of our current developer.