First, let’s use Python to set up two ICE attributes with DataArray2D.

si = Application
from win32com.client import constants as C            # win32com.client.constants

oObj = si.Selection(0)
a = oObj.ActivePrimitive.AddICEAttribute("MyString", C.siICENodeDataString, C.siICENodeStructureArray, C.siICENodeContextSingleton)
a.DataArray2D = [["a", "b", "c", "d", "e"]]

a1 = oObj.ActivePrimitive.AddICEAttribute("MyString2", C.siICENodeDataString, C.siICENodeStructureArray, C.siICENodeContextSingleton)
a1.DataArray2D = [["u", "v", "w" ]]

Now, let’s try to set DataArray2D with JScript. As a reminder, here’s how you access the DataArray2D in JScript:

o = Selection(0);
a = o.ActivePrimitive.ICEAttributes("MyString");
x = VBArray( a.DataArray2D ).toArray();
LogMessage( VBArray( x[0] ).toArray() );
// INFO : a,b,c,d,e

Seeing that, you would think that you could set DataArray2D using an array of arrays or maybe an array, but no:

a.DataArray2D =  [[ "a", "b", "c" ]];
// WARNING : 3390 - This ICEAttribute doesn't refer to a 2D array: <Attribute: MyString2>
// 

a.DataArray2D =  [ "a", "b", "c" ];
// WARNING : 3392 - Invalid offset specified while extracting data from this attribute: <Attribute: MyString2>
// <Offset: 110348408>
// 

At this point, I started wondering if there was anyway at all to do it, so I tried to put back the same value:

a.DataArray2D = a.DataArray2D;
// WARNING : 3393 - The input array doesn't match this attribute's data type or structure type: <Attribute: MyString2>
// 

Ack. Maybe if I converted it to a JScript array…well, at least something finally worked:

a.DataArray2D = VBArray( a.DataArray2D ).toArray();

Copying the DataArray2D from another attribute works too:

a = o.ActivePrimitive.ICEAttributes("MyString");
a1 = o.ActivePrimitive.ICEAttributes("MyString2");
a.DataArray2D = VBArray( a1.DataArray2D ).toArray();

So, based on that, I thought maybe I needed a safearray and things started getting a little hacky:

sa = getSafeArray( [ "a", "b", "c" ] );
jsa = new VBArray( sa ).toArray();

a.DataArray2D = sa;
// WARNING : 3392 - Invalid offset specified while extracting data from this attribute: <Attribute: MyString2>
// <Offset: 110348408>

a.DataArray2D = jsa;
// WARNING : 3392 - Invalid offset specified while extracting data from this attribute: <Attribute: MyString2>
// <Offset: 110348408>

//
// Get a safearray from a JScript array
//
function getSafeArray(jsArr) {
    var dict = new ActiveXObject("Scripting.Dictionary");
    for (var i = 0; i < jsArr.length; i++)
    dict.add(i, jsArr[i]);
    return dict.Items();
}

In summary, it doesn’t seem possible to set DataArray2D from JScript.