I try to adapt File Function Help Me!!

Hello I'm new Developer I need Help.

I want feature look like File feature.

I try to copy File Folder and rename to document.

I edit source code file -> document.

When i enable plugin It can upload (I can see file on server)

but when I click download It's have some problem??

Please Help me to see my source and what i missing

Thx u

http://www.mediafire.com/download/mxvz64eirer22k2/document.rar ..,, My Source 

Beginning Developers

Beginning Developers

This space is for newcomers, who wish to build a new plugin or to customize an existing one to their liking