A revealing essay by C.S. Lewis can be found either in his book, God in the Dock, or online: "Christian Apologetics". The relevant passage:
"I am speaking, so far of theological reading. Scientific reading is a different matter. If you know any science it is very desirable that you should keep it up. We have to answer the current scientific attitude toward Christianity, not the attitude scientists adopted one hundred years ago. Science is in continual change and we must try to keep abreast of it. We may mention such things; but we must mention them lightly and without claiming that they are more than “interesting.” Sentences beginning “Science has now proved” should be avoided. If we try to base our apologetic on some recent development in science, we shall usually find that just as we have put the finishing touches to our argument science has changed its mind and quietly withdrawn the theory we have been using as our foundation stone."
So would Lewis have rejected ID? No. Would he have made ID a major part of his apologetics? No, but he would have mentioned it "lightly" and claimed that it was "interesting."