Finally had the Free hub body on the Rook changed out as the Bike mechanic was busy with other things and we did not want to have the local dealer do the job.
We had some difficulty getting the Phillips screws undone that hold the hub to the motor plate, as they were put in using Loctite. The tamperproof Torx screws were also a bit of an issue as we needed special driver bits.
The hub changeover was because the original was making noise and the changeover solved the issue. The Rook is now working well.
Thanks again for the replacement hub. Great service and response from Surface 604. I would recommend them to anyone looking for an E-bike.