Spreadsheet APP for CI

Hi

I'm new to CodeIgniter and to MVC in general, and kinda getting into it and understanding it better by time. I have some questions

1)How do you integrate Spreadsheet API such as Google Spreadsheet into Codeigniter, or even better something like ZK spreadsheet into codeigniter (http://www.zkoss.org/product/zkspreadsheet).
2)Are there any CI applications with excel like spreadsheets that already exist and can take a look at it ?


Thanks