Oh frame by frame is built in, quick test

Would luv a small tutorial on this method if possible, it inspiration for an oldie i wanna do ;)

How u do this ?Amazing

After you paint with flex you just hold L1 and press left or right d-button to change frame, or its the cylindric icon with holes in the side on the tool bar, gives options for ghost image of previous frame.

What do you mean by next frame button? Where is it?