Thanks for the update, it is much better :-)
Yes I know that it is possible to open a document using the edit function. My question was related to view (as a reader) a document with an external viewer without having to edit (which is for instance not possible with RO licence).
I know it was possible with the old DW windows client. Such functionnalty would be more than helpful when a cutomer wants to view (only read) a document such as complex Autocad or SOlidWorks or other technical tool.