First - close basecamp. Then open it again. If basecamp was running when you installed the maps, then they will not show until you restart it.
My Trails is a transparent overlay that only has trails and POI. So, in other words, most of it is completely blank. Unless you're absolutely sure you are looking at a place with trails, that is likely the problem.
Have you selected the washington topo from the map dropdown menu? If there is no menu, right-click the toolbar and make sure "map products" is checked. Based on what you have said, you should see three items on the map menu
Global Map
My Trails
Washington Topo
If any of those are missing, then something went wrong with installation.