Tried to install the update via windows update, which failed, error message was "windows has encountered an unknown error".
Ran sfc /scannow which found no issues. After that finished running I zipped the CBS folder and have attached it here. (CBS.zip)
Then I tied to install the update via the standalone installer. This also failed but gave a different error message, which I've attached a screenshot of.
Then I ran sfc /scannow again, which again found no issues, and then I zipped the CBS folder again and have also attached that here (CBS1.zip) in case there might be any differences between the 2 .