We are connecting to a Siemens S7-1215 PLC at a customer site. That's the easy part of this adventure so far. When trying to add tags in Ignition using Browse Devices... under the Tag Browser of the designer, on the left we see a complete listing of everything down the lowest level of tag hierarchy in the PLC. However, when we look at the equivalent on the right side of the window as sown in the capture we don't see the lowest level of the tag definitions? I'm not that familiar with Siemens PLC data types and am curious how we get to those lower level attributes of the tags in the PLC?
You'll have to plan a little bit ahead, using UDTs, or using the regular OPC browser for drag and drop.
What you're seeing in the PLC is Variable Nodes that have child Variable Nodes. Ignition's tag system has no equivalent concept - tags cannot have children, only folders can have children (or UDT instances if you consider members children).
So you click the arrow to add the Status tag and it just adds the Status tag because there's no obvious place to place all the children, recursively.
Thank you Kevin Herron for the quick reply, even though it wasn't what I wanted to hear. 
It makes sense now.