Am trying to join mega 2560 to a toshiba 6560 driver

Hi all. I am building a 4 axis camera rig using 4 nema 23's which all works fine when running it through a tosh 6560 and powered by Mach 3. Howeever there is a specific camera application called "Dagonfame" using a dedicated GUI that aallows camera moves to be inputed directly which is better than using mach 3, in this application. ( see Google utube dragonframe/ arduino 6min video by "shutterbroke" ) He uses an easy driver,
I have 4 dual h bridge l298n boards which work fine when using Arduino program "stepper driver" which operates on pins 8,9,10 and 11 on the mega connected to the 4 input terminals on the dual h bridge. Perhaps I could use these but I have a 2 wire output ie. step and direction and these have a 4 wire input. Any ideas ?
The Dragonframe PDE file enables the mega to drive 8 motors but the pin out on the mega now uses direction pin 5, step pin 4 only and direction7, step 6 etc.
I would really be most grateful if any one could advise me how to wire this into the Toshiba 6560, either in the 25 pin out or the 15 pin out. I have read much on the web about dodgy chinese boards and there seems to be much discussion about the pin outs. I have printed out the pin outs for a 4 channel ( which I am using ) and also a 3 channel version and there seems little common ground between them so I would appreciate any guidance.
I have managed to drive a small nema 17 using an "easy driver" as this board uses a 2 way input of direction and step only which is what the mega 2560 is outputting, but you can fry an egg on the chip !!

Mant thanks