For my first effort in creating a UDK level walk through I developed this scene. It isn't overly action packed, however, I did learn a lot about the process of using Kismet and triggers to show/hide the HUD, destroy meshes and trigger animation events such as the doors being locked, and then opening upon finding the correct key.
All of the static meshes are original models made in 3DS MAX and most of the materials and textures are imported from MAX as well. I used BSPs to create the building and rooms, and then populated the scene and dressed it with the models from MAX.
This is a first effort and the total time to complete this entire scene was about 50-60 hours. This time, however, included the model construction, BSP development, as well as the learning of UDK and Kismet to implement all of the sequences I had mapped out as part of the pre-production.