well, I'm not completely versed in it, but I'll try to help along with what you are trying to accomplish.
From what I hear, you're trying to create a flexible array in the family editor. What you need to do is figure out the best way to create the formula for it. There can be different methods for this that work for different arrays.
Say you have an array width of 6' and you want something spaced out at 6" intervals. You create an array, selecting the model or detail lines or whatever you have and select "last" option and also the # of array pieces, then click where you want the last part to end.
In your family types, you usually have 2 parameters, one for say length of 6', the other says # of (whatever you have). The formula would go into the # of.... part as (length/(distance between your arrays). This will give you an integer, which is what you list the "# of array" part in.
This will create a label for you to select as a parameter for your array. You would click your array group, then select the part that has the label (# in your array) then up on the options bar, you now have a selection for your label as a parameter instead of unlabeled.
If you have trouble, there's a few threads on AUGI that have some integer arrays in families you can search out. I did see your post there, sorry I didn't respond to it. I don't go there much anymore.
I'd suggest some reverse engineering on these families. The one with the dentil moulding is a good one. Hope this has helped answer some things.
http://forums.augi.com/showthread.php?t=2395&highlight=family+array
http://forums.augi.com/showthread.php?t=59495&highlight=family+array