How to Upload Document to SharePoint document Library from k2 smart forms?

Dear,

I am involved in developing a project using K2.

Can some one here please help me to solve my following burning issue realted to share point?

1. I want to upload documents to Share point document LIbrary

2. I want to read the uploaded document

3. I Want to download the document.

4. How do i pass the share point document details to a database table?

Thanks,

Lafi