It seems like you do not have any attributed imported to your nodeset/network.
When you are in the main ORA window under Meta-network Manager expand the network in question -> select your nodeset -> select editor and if you only have Nodeset ID column that means you do not have any attributes affiliated to your nodes.
However, that is an easy fix - when you are in nodeset editor you can either press attributes -> create new attribute and manually enter all of the attributes per node; or attributes -> import attributes and import them from an already existing file.
Once you have the attributes you'll be able to color nodes in the visualizer.
Hope this helps!