Sort culture or language in specific order

I am afraid but the language data source web part/control does not have the property for sorting/ordering. The cultures are sorted alphabetically by default. IF you want to change the ordering, you will need to create custom data source web part and get the cultures from the DB and sort them as you want. You can get the URLs using code like this (from the default language selector):

if (Node != null)  
            {  
                string url = URLHelper.RemoveQuery(RequestContext.CurrentURL);  
                documentCultureURLs = DocumentURLProvider.GetDocumentCultureUrls(Node, url, ExcludedCultureCode, UrlOptions);  
            }  
return documentCultureURLs;