By now you should have started TkHol, and be looking at the Theory Viewer. The purpose of this tool is to allow you to navigate around the hierarchy of theories loaded into your session, and view the contents of each theory as well. It also serves as the launching pad for many other actions in the system.
Figure: The startup display for TkTheoryViewer
You are probably looking at the HolPlus theory, which acts as an ``amalgamating'' theory for several other theories. The theory contains no theorems, definitions or axioms of its own, hence the windows to display these are not automatically opened.
Take the time now to browse around the theory hierarchy. You can do this with the mouse:
NOTE: The first time you display a theorem, term or goal, TkHol needs to set up some initial translation tables. This can take a few seconds. This only gets done once per session.