The Page builder , Interop , Transport services in the front end services are pointed to the system alias of the backend instead of Local. (These are the front end services and should refer to the frontend) This created a mismatch for the hash key values comparing with the values in the table at USOBHASH for reading the metadata and throws an error of 404 .
Also making sure of applying the notes mentioned here and debugging the logs in browser console has helped.
Regards
Virinchy