Package Fail: CompressedFormat == PF_Unknown || CompressedFormat == CompressedMip[0].PixelFormat

You are not alone in this Unreal Engine 4.27 Preview - #193 by motorsep

I reported the bug, pinged Epic and @VictorLerp on Discord, but haven’t heard anything back. Let’s hope it will be fixed (preferably in 4.27 hotfix or something).