In my limited experience -- and I don't think mine was Kentia Palm specifically -- I found that palms need more light than is usually assured by the houseplant books. Especially because of the size and spread, they completely block the light from the side not facing the window. Turning the container a 1/4 turn a day helps -- a turntable or a wheeled platform is useful for larger plants. But I think it's far better to provide supplemental light with fluorescent tube light mounted vertically on the wall. If the plant is situated in a corner, windows on both walls could help. In one apartment, I made a mirrored corner next to the window with mirror tiles, and put a floor lamp in the corner.
Another essential was humidity. Until the palm got too big, I wrestled the container into the bathtub and showered the plant once a week, watering it at the same time. After it became apparent that it was impossible to move the fully watered plant and container, I had to mist it, but it was inadequate and it didn't take long for the spider mites to infest it. (Misting also added to the workload because the mirrored wall and window always got spotty and needed cleaning