If you want to open DCr in edit mode then, with every DCR in the list having a "Edit" link in the list of DCRs, just click on the edit, it will open for you in edit mode.Hope this helpThnaks Nicholas
Probably you selected the check box for the DCR and then you right click on the preview button saying "Open in new windows", this means you are opening a new window to see the preview but there it is not getting any file selected (as opening in new window)If you select a DCR and simply click the preview button you will get the DCR to open in read-only mode, next if you want to open it in edit mode click on "EDIT" link followed by DCR name.Hope this will clear your doubt.Thanks Nicholas