I'm replying myself a little bit :D
I've read in a post that I can't see the Edit button because my browser is Firefox, is this true??
I've installed the Update for the Office Add in for Vista and now I can see the shared workspaces, however this is what happens...
1) I click the Office button (2007)
2) The click "Open from Office Live"
3) Then I click "Sign in ...." and I sign in
4) Word freezes a little bit and then shows me a Open dialog with My (local) Documents
5) Then I repeat steps 1 and 2, Now I see the workspaces in the Office menu (on the right hand).
6) I select one, an open dialog opens but I see no documents at all!
What's going wrong?