I believe I've accidentally stumbled across a hack for this. I had my email template as 'Dear {{customer_first_name}}{{customer_business_name}},' - i.e. expecting the email would pull the first name of an individual customer or the business name of a company.
But then we had a 'Company type' Customer where the email was populating both fields - previously advised to be not possible.
After some back-and-forth with Support they suggested I change the Customer Designation to 'Individual', and sure enough - the name fields were populated.
So the hack is: change a Company-type Customer to Individual, populate the First Name, change it back to Company Type and then an email template using {{customer_first_name}} will pull that field out of the Individual data.
