I have a problem with using multiple workspaces on Ubuntu 12.04 with Gnome (and indeed Unity).
I have been playing with Compix to enable some effects, while using Gnome session fallback.
Previously I had 4 workspaces and could navigate between them with no problem.
Now, when logging on to gnome I can see the 4 workspaces in the bottom right but can't switch to anything.
When logging on to Unity I don't get any multiple workspaces, just the one.
I have tried changing the workspace configuration via Compiz and Ubuntu Tweak etc etc but still can't reenable anything other than 1 workspace.
Any offers? Not a major issue but I like using multi-workspaces and wish I'd never touched Compiz now!