I'm running PS 220.127.116.11, but looking to upgrade to 18.104.22.168. Unfortunately, the autmated upgrade process is not working and I've tried several different manual upgrade processes, all of which have failed in some way.
It looks like the only way to upgrade would be for me to do a manual export from the existing store and import into a new version. However, I don't know how to do this.
Could anybody tell me whether it is possible to migrate between the two versions using Prestashop Store Manager? If so, how? I can export/import products and categories, but can't see how to migrate customers and orders.