The settings provided by the MailMergeOptions property are used by the MailMerge method, unless specified explicitly in the options parameter.
To perform a specific mail merge with options different from ones specified using the MailMergeOptions property, create a new DevExpress.XtraRichEdit.API.Native.MailMergeOptions instance using the CreateMailMergeOptions method, specify its property values as required, and call the MailMerge method overload with options.