Memory is a bit fuzzy here but wasn't there a difference between the 05-07 and 08-11 MAF tubes? Steedas SRI kit came with a removable insert of sorts for this reason?
K&N also had issues with their MAF tubes being off in diameter, throwing off the MAF reading a bit. Perhaps this issue is present with this intake as well?
I wouldn't think you would need a tune to deal with just an intake. You are not drastically changing anything from stock except a more direct, and free flowing path of airflow to the engine and the cars adaptive learning strategy should be more than able to compensate.
I would start by making sure everything is tight. Make sure the MAF is in the right way. If those conditions are met, I would pull the MAF out and look at the sensor wire in it and see if it has been contaminated by the filter oil. If its oiled too much, oil film can make its way onto this wire, bake on it and cause bad readings. Take some special MAF cleaner to it if you suspect its dirty at all.