Private Sub cmdSendEmail_Click()
    Dim res As TNZAPI.MessageResult
    
    Dim message As TNZAPI.Email
    Set message = New TNZAPI.Email
    
    message.Sender = "YOUR_EMAIL_ADDRESS"
    message.APIKey = "YOUR_API_KEY"
    
    message.FromEmail = "from@test.com"
    message.EmailSubject = "Test Email"
    message.MessagePlain = "Test Email Body"
    message.Recipient = "email@test.com"
    
    Set res = message.SendMessage()
    
    MsgBox "Message ID: " & res.MessageID
End Sub