The description I have of the shuffle kick comes from the IANTD Technical Diver Encyclopedia. It's basically what most of us refer to as a modified flutter...with bent knees (the skydiver like position) an the fins are kept well above the divers horizontal axis with the kick commming from the knee rather than the hip as sometimes taught in recreational diving.
The kick that I think of as a shuffle is essentally the same only with VERY little vertical motion...mostly horizontal with a little bit of fin tip flex providing the propulsion.
IANTD describes the modified flutter as a flutter where the fins remain but could extend to the divers horizontal axis.
The heel toe kicks or ankle kicks are modified flutter kicks where the kick is driven from the ankle (very little motion.)
I would consider any of those as modified flutters and there are other variations, though, I can't think of which book they are described in, such as one legged kicks. Besides situations where you might only have one leg that's working, the one legged kicks can be used with the nonkicking leg used to block the wash from the kicking leg and is useful in ver small silty areas where you can't get your feet up very higb but also can't have fin wash blasting the bottom.
Those descriptions/names are a little different than what you see from some other agencies like the NACD, NSS-CDS or GUE.
I can't be much help with the dolphin kicks.
