1. Yes Wipe all except SD Card. 2. SD EXT is where DT a2sd stores your apps 3. android Secure is where some apps get stored, like angry birds. Not sure the real reason why, I think it just has something to do with the size of the app, not sure though 4. DT is part of MikG yes, all a2sd reinstall does is ensure that all the flags are in place for your apps when you install them, be sure to do this before you restore apps. You may not have to run that command but it doesn't hurt to do it just to cover your bases, because technically Mik's roms, DT, recognize the sd ext and automatically put them where they need to go, but I just like to be sure.