On the chromium 57 thread pythoneye2 gave a link with an extraordinary solution - which worked! On chromium type with HW keyboard. Nothing shows. Press the shutdown button to open the menu. Tab on the chromium screen to get it away. Suddenly have both HW keyboard working and access to MyDocs folder in window mode chromium. Just posted a picture to my friends with N900 on whatsapp. My moment of success on this forum.