A UDL is technically a text file, so you could open it with "Read Characters from file", put the result string into a string control, edit it and save it back using the "Write Characters to File".
UDLs however have their own configuration dialog embedded in the Windows OS. You can use this dialog in your LabVIEW application. The attached VI shows how to create a new UDL. You can edit an existing UDL by switching the method node to PromptEdit and wiring in an open ADO connection reference.
