Actualy, According to Kyle (the artist), this takes place after the cremation while Rhinox is putting everything away. So yes, Dinobot has already been cremated before panel one.
They could have done making that a bit clearer. I only figured out it had something to do with Dinobot's funeral from the text, the device just looks like a random widget.
Well, I just did the colors and letters. I haven't seen that episode so I don't know if that's how the actual device looked or not. It does look like some form of burner though.
Yeah. You have the pan in which things burn, and the two fuel tanks, and pipes that connect the fuel to the burner pan. At least that's how I interpret it. Like I said though, Having not seen the episode, I can't say for sure how it works.