If you have both downloads, I've simply used Add-On with the traditional method and moved the appropriate items over to their applicable folders in the interim. Of course that means there's no installer for the zips, etc... That's a manually process. For larger items and direct installs, you may want to hold off, but for the simpler tasks, i.e. skin files, that's a pretty straightforward process. I can help with some of those tasks if needed, just shoot me a PM. I'll tell you I don't know, if I don't.
