I'll try to answer in an organized way..
The VW paint is usually pretty hard so don't worry about getting too aggressive with it.
The #9 is so mild as to be (virtually) functionally nonabrasive on hard paint unless you use it with a rotary, so don't bother with #9, use #80. You might have to use the #80 numerous times- again, with that paint don't worry about being too aggressive, worry about being aggressive enough. You might want to use #83 or #2 (new version) on any bad marring just so the job goes quicker and then follow up with the #80.
The orange pads aren't all that aggressive, you should be OK with that. But it won't add much to the cut of the #80 and is really better suited to a more aggressive product.
If you use the orange, I'd follow up with a polishing pad (#80 oughta be just right on that).
Work the #80 until it starts to go clear/translucent. Buff it off before it dries completely.
The #80 leaves lots of Meg's "trade secret oils" behind, so I dunno if you'll get any benefit from the DC#2. Note that DC #2 is a nonabrasive product anyhow, so it won't really matter if you apply it by PC or by hand; all the Meg's "pure polishes" (#3/#5/#7/#81/DC#2) work fine by PC or by hand. Don't let these dry all the way either (except for #5), buff off while still a little wet.