change DCA for attribute properties set checkbox "Customize the file tree" and the "Set file root folder" at least - "Valid file types", "Allow files only" should not be dependent on the checkbox
hmm - the checkbox ""Customize the file tree" " is necessary at all?
Explain what you want to get changed or do it on your own. I do not understand what you want aside from "something in the DCA to be changed".
we discussed this at the MM call: the name is a bit confusing - especially in german with "Dateibaum". This is where "file widget" ("Datei-Widget") should be, since it is the settings of the whole widget.
wen can change this after release MM 2.2 by transifex