How do you figure that? My demon flip mix ups seemed useless because of that stupid headbutt into ultra, which seemingly doesn't trade but cleanly beat all of the demon flip options. Maybe it's about time I learn the air hadouken cross up mix up.
akuma vs rog can be a little rough, once you get the knock down you can really bully him. You wanna go into training mode and get the timing down for safe jump palm, and also add on os sweep. It covers every option, so once you start to make him just block, then you can dominate his face. Just remember rog has a stupid hit box, so experiment with combos that will work on him at certain ranges.
Oh, and if he's one of those bad rogs that plays the STUPID aggressive game. (across screen ex rush punches, that stupid overhead) Make sure you do low forward buffer in DP when you see an ex rush punch coming at you, and for the overhead just make sure you block that thing, it's so **** slow. Either that or DP through it if you see him going for it
and about the air fb mix up...yeah, it's not really gdlk or anything, you can only do it after certain situations. You can use it after a palm hit, and after a demon throw. For the throw you wanna dash up once then do the TK air ball, for the palm you just back up a little then do the motions. You could also be a little flashy and go for srk fadc then Tk air ball, that looks sick.. but you're gambling with 2 meters. Jus do it if you know they're free<3
edit: forgot to add another really good & easy safe jump setup. After a sweep, if you hold up forward and do the command dive kick, it'll safe jump every reversal that is 5 frames or slower. (adon and deejay are the exceptions)