Hey, Doncha, quick update: I found that first of all SC is a formidable bit of code 😉 and that if you supply it with a fresh get variable, that that solved my little problem. If you want a copy of my plugin, let me know. Does seem like a timely issue maybe as there seemed to be no real working theme switcher that would work with SC!
So anyway, I ended up tossing the plugin I was writing for SC and just making sure the one I already wrote worked… (with SC).