Here are further ways in which Zhuangzi's philosophy differs from Buddhism as articulated by Wu (The Butterfly as Companion):
3) Both understand ignorance as a cause of suffering. "The Buddhist awakening to knowledge dissolves our ignorance. Chuang Tzu's awakening to uncertainty (are we dreaming or awakened?) amounts to our knowledge of ignorance, affirmation of uncertainty." Buddhists believe they can come to know Truth and are thereby relieved of their ignorance. Zhuangzi teaches that no such Truth is within our grasp and that this essential not-knowing is where our liberation lies; we become free in our tenuousness by abandoning the futile search for solidity and by becoming that very tenuousness.
"Buddhists awaken out of dreaming; Chuang Tzu wakes up to dreaming." I have often attempted to make this point. Though Zhuangzi and Buddhism agree that we live in a world-made-up, Zhuangzi does not propose the possibility of ceasing to dream. Rather, we wake up to the fact that we are dreaming and recreate the world we dream. Perhaps this is why words like "wandering", "frolicking", "playfulness", and "laughing" so readily come to mind when considering the spirit of Zhuangzi.
4) Both understand clinging (attachment) to be a cause of suffering. "The Buddhist unclings himself to go beyond existence, even that of himself. Chuang Tzu unclutters and empties his self to tune in and partake in the pipings of all (men, things, heaven), to treasure and follow things . . ." Buddhism seeks detachment to escape things, Zhuangzi in order to more thoroughly embrace them. Attachment is manifest in preferences. Zhuangzi declares the equality of all things and consequentially the acceptability of all things. Unstuck from "benefit and harm", the belief that things (events) can rob us, one is free to mount and happily ride upon them all.
5) Buddhism seeks to dissolve identity altogether. Zhuangzi seeks only to unfix it; now a horse, now a cow; the point is to enjoy what one presently is while gladly accepting and enjoying changing into something else. The emptied self is a self nonetheless — while it is a self.
Wu sums up with a quote from Liu Xianxin (1896-1932) to which I have also made frequent reference: "The Buddhists stressed the emptiness of all, discarding all; Taoists stressed the greatness of all, wanting all." Here, we see these two philosophies at their most extreme divergence. Liu saw no possibility of reconciling the two. And yet, amazingly, they have so much in common — if only we can understand them outside the context of objective rightness and wrongness. But such a perspective is not so easily adopted by those who believe that Truth is to be had. Traditional Christianity, for example, is unable to accept other points of view solely on the basis of their effectiveness; and Buddhism, I believe, is ultimately also unable to do so.
You can check out Scott's writings on Zhuangzi here.