EndNote X8 Keeps Crashing on Mac

After upgrading my MAC os to High Sierra 10.13.2 I find out that Endnote X7 is not compatible and just would not open, so I have just paid for the upgrade to X8 to find that this crashes instantly with any attempt to interact with it.  This really is not fair, although I have submitted my PhD thesis I have my viva next week, so desperately need to be looking at my stored references. I also need to be subitting manuscripts and rely on Endnote for that.

I’ve tried the upgrade fix, no joy.  I’ve tried syncing with a cloud version but they do not match and contain fewer references.

Please tell me there is a solution, otherwise I will attempt to take my 2000 references and switch to another referencing manager!!