The files you attach can be of any type: documents, spreadsheets, presetations, video, images, zip files.... It's all good.
Kerika+Box: Kerika automatically uploads your Kerika files to your Box account, and arranges for your Team Members and Visitors to get the right access to these files.
Direct signup with email: your files are stored in a special Google Drive account managed by Kerika. You get your own, access-restricted folder within this Google Drive account, and as you add Team Member or Visitors to your boards, Kerika takes care of all the access permissions.
As you add or remove people from your board teams, Kerika automatically makes sure everyone has the right access.
You can also attach any kind of Web content, from your Intranet or the public Internet, to any Kerika card or board.
(And, yes, that includes files that you have stored in SharePoint: these also have URLs that you can use to attach your SharePoint content to your Kerika boards.)
When you add a URL, Kerika figures out what you are adding, and show it in the best possible way: videos and images, for example, show up with small thumbnails to make it easy to see what's attached, at a glance.
If you working with Whiteboards (which you can attach to individual cards on a Task Board or use as an independent Whiteboard) you can attach files and Web content right onto the canvas, as shown in this example.
As with adding URLs to cards, Kerika shows a small thumbnail of the content which you can resize, and incorporate into your process flow diagram.
Not just cards and canvases: you can also attach content to the board itself.