Adding Tags as a custom field to listing

In 7.1.4 tags could be added by client as part of the listing process as well as by Admin.

This was highly effective for our directory as many of these tags were found and ranked by Google increasing the number of times the listing was found.

However tags is now a widget in Responsive theme. I would love to add tags to the listing process but not sure how to go about this.

Ideally I would like to import all the previous tags from 7.1.4, but not sure this can be done.

I tried to add tags as a custom field (taxonomy) however this has not worked and I am now going to have to remove all the custom fields and re-do them as I cannot find a way to remove the taxonomy.

Has anyone any ideas on how this can be fixed? Any help appreciated.