e.g.
https://docs.unrealengine.com/latest/INT/Engine/Landscape/QuickStart/5/index.html
or
https://docs.unrealengine.com/latest/INT/Engine/Landscape/QuickStart/6/index.html
results in
400 Bad Request
also many images broken in
https://docs.unrealengine.com/latest/INT/Engine/Landscape/QuickStart/4/index.html