Word for Mac 2011, Endnote X 7.7.1 and High Sierra problem

I notice people reporting problems involving Endnote and Word for Mac 2016 after updating to High Sierra that seem to be identical to the ones I am experiencing.

I have two MacBook Pros:

(A). 2011 model running OS X Yosemite 10.10.5, running Endnote 7.7.1 and Word for Mac 2011 version 14.7.2

(B). 2018 modewl running OS X 10.13.3 High Sierra, onto which my Endnote 7.7.1 and Word for Mac 2011 version 14.7.2 have been migrated.

On machine (A) CWYW works like a dream, and so does everyhing else about Endnote.

On machine (B) Endnote 7.7.1 works (on its own) and so does Word for Mac 2011 version 14.7.2 (on its own).  However, Word lacks the CWYW facility, and Endnote no longer appears in tools.

I spent over £100 on upgrading to Endnote X8: no improvement.  Yes, I did try running Customise from X7 and X8, trying to copy bundle files into the correct position manually, and so on and so forth, plus activiting thigs from the Templates menu item.  I can then see Endnote in Tools for a while - but try to insert a citation, and Word crashes.  When Word restarts, no Endnote Tools or CWYW.

Will this go away if I upgrade to Office for Mac 2016?   I don’t want to spend more money for no result!

And why is all this happening???