Only on this workspace issue

[Peter Craig]

Hi, I am new to Linux and am now using Linux Mint 13 MATE. I have installed compiz and all the relevant addons in order to manipulate the desktop environment. I have set up a cube with 4 workspaces and it is functioning correctly and I am able to switch between these workspaces as I should. My problem is that I can view all open windows in the menu bar on all workspaces, but I only want to view the windows that are on each individual workspace. When I right click on a window in the menu bar the option "Only on this workspace" is already selected. How can I change this?

Thanks in advance,
Peter Craig