This is a tip to avoid a lot of frustration when using an Object Node.
The problem with this node is that it doesn't always reflect the expected ports.

Follow up:

I have made a little setup to make my point.
It is a very basic setup with a null containing 3 cubes.
In my xpresso I made a hierarchy node to point to the cubes.
So far so good, well no!!
Look at the ports on the object node, they do not reflect the expected ports of a cube. That is odd.
The strange thing is that the whole setup is 100% correct (you can check the name port on the object node and it will confirm it is a cube)

Here is the solution.
To make the object node do what you expect you have to help xpresso a bit.
You have to drag an example object in the editor (in this case a cube), reconnect the hierarchy to this node and everything works as expected. All the ports reflect a cube alright.

The point I am trying to make is that xpresso does not update the ports on the object node as expected.