1. Could you explain the purpose of the dynamic Array ? 
The dynamic array is the information that is pulled from the recordset. It is a two dimensional array. it is an array of values from the parent list, with a subarray of values that will be used for the child list.
2. In one instance you state that the update page is similar to the insert, except for the body onload event where the set selected in list for the parent list and populate list from array are to be added. Does that mean the dynamic array, dynamic menu on parent and the onchange behavior on the parent select are all the same?
yes, they are the same dynamic array, It's just a diferance of when they are used, onChange, or onLoad:
In a regular page, you would populate the parent list, then when the parent list value is changed, use the onChange event to populate the child list from the array based on the selection that was made.
on an update page, you want to have this happen the page loads. in other words, automate the process of selecting a value in the parent list, populateing the child list from the array, then making a selection from the child list.
to accomplish this, you use the body onLoad event. The first Set Selected In list behavior automates the process of selecting a value from the parent list, the Popualte list from array behavior automates the process of populating the child list based on the selection that was made, the second set selected in list behaivor automates the process of makoing the selection in the child list.
3. Could you explain what the purpose of the “populate list from array” and “set select in list” are and how they must relate to the dynamic array?
the set selected in list selects an item in the parent list, it selects the item to use for populating the child list.
like i said in the first question, the dynamic array is a 2 dimensional array, the first dimension contains all the parent list values. The second dimensions contains the child list values, when a parent value is selected, the array returns the items that relate to the parent.
