How to edit file extensions in "documents" category (and maybe others)

I needed to add the .lwp (Lotus Word Pro) extension to the Documents Category as these were not being included in any category. (Chat support was useless in this).
Found that there is a file on each computer were this can be edited to include other extensions.
In Windows 10 the file location is “C:\Program Files (x86)\Western Digital\WD SmartWare”
The file that lists the extensions for the documents category is “documents.xml”.
(I had to create a copy and edited it outside of this folder before saving the new-version in the folder).
I used Notepad as an editor and added the "
.lwp" extension in the alphabetical order there and saved it.
I then DISABLED SW backup, restarted the WD Backup SERVICE, and re-enabled the SW backup.
Next I moved to review the missing files locations in the SW backup location on the WD Drive (not my PC location) to verify that these were now being included.
*** This took quite a while to confirm, as when the SW software apparently goes through its indexing again once it is restarted.
Hope this works for others