Thank you for contacting us via the forum. I'm sorry to say that Android devices treat external storage locations differently, so sometimes SmartOffice has difficulty "seeing" the SD Card.
One thing to tell you is that the "0" location, at least on the mobile devices I test with, refers to the internal storage of the device. This gives the user access to every folder and every file on the device through the SmartOffice File Explorer.
If SmartOffice can "see" your SD Card, it will likely show up as a different drive from the "0" location, possibly a "1".
If you would like, you can send me a screen shot of your SO File Explorer and I'll review it. I'll send you an email message off of the forum to which you can reply.