azzd, time alignment is hard to get it right down to a sample either way. I think you will find your IACC will increase with time alignment. For sure, a 5 way is a daunting task, but it should pay off. I agree with Rod's assessment of time aligning drivers: http://sound.whsites.net/ptd.htm
I have to tell you it took me three tries to get it in the ballpark of understanding what was going on. My book in the sig has a much more detailed step by step than he article you read. However, I am happy to assist if you want to PM me, when you are ready. Really nice speakers, would be a shame not to have the drivers timing nicely integrated, especially since you already have the digital XO.