If I play with this long enough in my version locally when I "Move" a node from left to right, I can reproduce

Microsoft JScript runtime error: Unable to get value of the property '0': object is null or undefined ( shown at the bolded line below)

I believe it is when you move say item #5 and then move ANY item ABOVE where that was (like item #3).  It is like "the moved" elements are still being referenced by their index offset.

Is this a bug in set_value?  It should at least check for null before that array reference.

set_value:function(id, val, address)
{
var index = id[0];
var defaultVal = id[1];

if(typeof(val) == "boolean")
val = (val)?1:0;
var item = this._items[address][0][index]

if(item == null)
item = defaultVal;

if(!$util.compare(item, val))
this._transactionList.add_transaction(address, val, index);
else
this._transactionList.remove_transaction(address, index);
},

It seems not to be client-side as I was asking.

Hi,

Any luck with the control?

Please let me know if you need of help further.

Best,