so what you will want to do is go look up maf scaling on romraider or nasioc. There is a cool tab when you load your rom and open the logger in romraider called MAF. It takes the correction and plots it on a graphs so you can see overall where its adding and taking away fuel. Closer you get to 0 down the load column the better it runs.
What i start out doing is start the car up. warm it all the way up and look at correction. if it says its taking out -15 then i go to the maf scale. I do select all and press - about 15 times. Reflash and repeat. You will eventually get it pretty close to where you want... Then what you do is save that rev and load it in romraider. take the car for a ride while logging in that maf tab. Interpolate when your done which will take the averages and draw a great line. Take from... like 1.5ish to 2.8 or whatever looks like a "real" average area and update it.
Last load the rom back into ecuflash and open the maf scaling again. Click the show graph and make sure there isnt a magic jagged line. it might be climbing up to say 60 grams and then drop to 47. find that "47" on your graph select that and everythign above it and press + until you get to where it looks smooth.
Then if your still not sure, pm me and ill give you my email. I can double check so you are good to go!.