Contacted Crossover and they advised me as follows which worked:
"If you log into our website, you can download older versions of Crossover here
http://www.codeweavers.com/account/d...s/?_dl=archive
I would suggest you install Crossover 12.5.1. Then when it is installed, open Crossover and click "Crossover" from the top menu bar. Select "Preferences" and choose the "Updates" tab. Here just uncheck the "Check for Crossover Updates" and you will able to remain on version 12.5.1"