Recover data afer failed upgrade

I hope that someone can help otherwise some months work has to be re-done

Firstly – me – I am not a professional but have been developing with drupal for some years as a volunteer

I developed the start of a fairly complicated site using Varbase and thought that I had backed up everything prior to updating from Varbase 8.x.4.09 to Varbase8.x.4.10. The upgrade failed and I posted this under another question and also on the Varbase distribution. So far no action.

So there are two questions

  1. Is there a way of recovering the node data so that I can use it on a new site or alternatively is there a way of altering the mysql database so that I can go back to the original version
  2. Is there a way of changing the database so that I can used vanilla D8 modules

I would really appreciate help on this as it has made be very depressed that I have lost so much work

Drupal version: