I've got an odd problem for which I've been looking for a solution for about 2 weeks now. This is my final attempt to resolve it before implementing a less attractive alternative. I'm using an AdvancedDataGrid component to render a grouped data collection. The Nodes and children items render perfectly. They are grouped according to a date string and this all works just fine. The problem pertains to the tween effect when a node is expanded. The tween effect plays for only the first node. All other nodes simply pop out when opened (they open and close correctly, but there is no animation showing them "sliding" out from under the root). I've experimented with various openDuration and openEasingFunction configs to no avail. I've located the validateNow() call in about a thousand different locations to see if this would have any affect (it did not). One thing I've noticed is that the node for which the tween effect plays has only about 15 child items where the nodes that won't play the tween effect contain tens of items (20, 30, or more). Is this a bug or intentional limitation of the ADG component? Any clues would be greatly appreciated. This issue has been driving me crazy for weeks and I think I've read every ADG related blog post written in the last 3 years.