It's working!
After reading through the Lichuan LC10E thread (
forum.linuxcnc.org/ethercat/52341-proble...ethercat-servo-drive
), where somebody discovered that the issue is around how the clock is setup, the key are these missing lines from my xml -
<syncManager idx="0" dir="out">
</syncManager>
<syncManager idx="1" dir="in">
</syncManager>
Added those for each slave, and all the drives now intialise and activate when LCNC is opened.
Now to decide if I want to re-retrofit them to my little mill, or buy an extra drive and motor for the plasma table I have part built..