Oh no after a day of figuring out what to do, there is nothing at the link provided!

This FAQ page used to be sticky, but , in their wisdom, WD decided not to make it sticky again after a recent forum replacement.

It contains what i’d suggest is the definitive guide to disabling the wdmcserverd etc functions:

/etc/init.d/wdmcserverd stop
/etc/init.d/wdphotodbmergerd stop
# to keep it from restarting after a reboot 
update-rc.d wdphotodbmergerd disable
update-rc.d wdmcserverd disable