the Dreamweaver insert record behavior will not be configured to allow for an unknown number of characters since it uses parameters in the query. One of the arguments that MUST be passed to the parameter is maximum length. This has nothing to do with the DB Column, it is a restriction to the ADO Parameter.
You can either set the parameter to use a very large max character setting:
MM_editCmd.Parameters.Append MM_editCmd.CreateParameter("param3", 202, 1, 5000, Request.Form("NCnews")) ' adVarWChar
or change to using the data assist insert record behavior which does not use parameters.