This can be painful on complex projects. Beware. For the brave folks, here is the recommended path:
Let’s say you have a site running CSS Hero v2.something.
– Launch the CSS Hero editor (v2).
– View the generated code and save it in a safe place (like your clipboard)
– Disable the CSS Hero v2 plugin – and delete it.
– Download latest v3, install and activate.
– Launch the CSS Hero editor (v3).
– Open the Code Inspector using the icon the very top menu bar, left side.
– PASTE the whole code to your clipboard.
– Save and publish