Hello,
Many of the shortcut keys no longer work in Ubuntu 14.04. For instance, Ctrl+S does not save the project, I need to go to the menu and click "Save"
Edit: I would like to add that it seems like the reason is that modifiers don't always get released correctly. For instance, doing Ctrl+Alt+Right to switch workspaces seemingly makes Spine think that Alt is still pressed when I go back to it.