The path to Civitella Alfedena from the Comisciara is well route marked from the Comisciara area of the park:
From the car park entrance to this area of the national park walk about 30 mins along the road - now closed to traffic. View the waterfalls and then backtrack halfway down the road til you see a marker for route G4.
At first the path enters a wood but then becomes more open. Near a water trough there is a junction for G3 (sharp left) take this if you wish to go back to the Comisciara otherwise continue on the same path, which now becomes path I2, into Civitella Alfedena.
The path down into the village is fairly steep so view the town on your way down to avoid climbing back up again in the heat!
Its not a long or difficult hike - although the first bit can be a bit muddy from the rain. The hike took less than 2 hours - including a picnic stop halfway.
A pleasant hike can be made from the Comiscara area of the National park - where the waterfalls can be visited first - to Civitella Alfedena. The path is a lovely mixutre of climbing up through the trees for a short while, an open meadow with great mountain vistas -perfect for a picnic spot - and a level path around the hill before dropping down into the village itself.