In Mail>Receipts>New>Fields to Include Tab, the constituent name should be added as a possible field to export (merge). While it's fine to use the addressee field or salutation field in a letter, it's necessary to have the constituent's legal first name, middle initial, and last name on a receipt as that is what is required by the government. See CRA Tax Receipt requirements. Often the addressee is their preferred name and not always their legal name.

This would be useful to all Canadians who create custom receipts in Raiser's Edge and probably many Americans who use custom receipting.