One thing to mention about the clay technique (and any washing, waxing,sealing, etc,)....
Always stroke in the direction the wind would go over the vehicle,ie: front to back, never side to side. I had a big argument with my dentist about this (not the brightest thing I could've done on the day I got my bridge installed....
) He's a disciple of the Old School Porsche Germans-make good-everything-else-is-crap mantra, and he finally agreed that side to side is bad simply because the dust and dirt we drive through every day will embed itself in the ridges formed by the wax buildup - sure it sounds far-fetched, but logically, unless you do handbrake turns for most of your commute you normally drive in a forward motion drilling holes in the wind. Taken to the extreme, this would automatically create swirl marks because the wind is hitting the wax at a 90 degree angle rather than grooving along with it. Like others have stated here don't do ANY circular motions when washing, rubbingout, drying, or polishing, - it just adds to the problem. Always go front to back (and, yeah, my tailgate gets the side-to side simply because it's easier and doesn't get as much wax on the cladding, but I do my kid's Tahoe up and down because he's got the barn doors on it).
A wash mitt is fine - I just suggested the sponge because of the water factor - you need to virtually deluge the surface to get rid of any remaining Dawn, and a sponge will help in that regard. A microfiber mitt holds almost as much water anyway, so stick with whatever you're comfortable with.
A washdown after claying will remove any clay film that might remain on your paint. Remember the addage "95% preparation - 5% whatever...."...If you've prepped the surface correctly you should only need one ounce of Z5 (or Z2) to do two coats on a cladded Av (I've never done a nekkid one). The sealant should glide on easily. Also, don't use too much - it's too expensive to do that, and it's doesn't help or make it better. A filmy or slightly cloudy appearance is best.....that's also why two coats works better, in case you missed anything the first time around.....
Orange peel is the perfect description for a paint condition that came that way. You didn't cause it or make it worse. AFAIK it's caused by an underapplication of the color coat allowing some of the primer to appear to "wrinkle" the color in certain areas, and it wasn't corrected by the time the clear was shot over it. Bad mixing, moisture in the sprayer, lazy robots, anything can cause it. If you can't find it, great.......
Man, my digits are sore.....gotta stop typing now and get a cold Mike's out of the fridge....then I won't be able to type at all.....but I'll feel great.
Later.
Jake