[Phanx]

Those errors would indicate that kgPanels is loading your panels before Stuf has loaded. If kgPanels has a "dependency" field, add Stuf to it. If not, add this to your OnLoad script:

if not INSERT_STUF_GLOBAL_HERE then
     LoadAddOn("INSERT_STUF_FOLDER_NAME_HERE")
end

If that still doesn't work, it can be made to work; it'll just require more code.