Well, it’s mostly in regard to the influence of process theory on philosophy and theology, especially the influence of Alfred North Whitehead. In effect, process theologians deny the Incarnation of Christ in the individual person of Jesus. Advocates of process theology are also prone to religious indifferentism, arguing that all religions are manifestations of Divine providence, and that all Scripture is just human interpretation of the Divine rather than an example of God giving infallible guidance. There are many other examples than this. One can see how these opinions are irreconcilable with Catholic doctrine and philosophy.
If you’re interested in an analytic criticism of process philosophy and theology, I must admit that it would be far beyond the scope of my abilities. I wonder if there are others here more capable than I who could help, if that is even what you’re looking for. But I hope that at least show you where problems arise between traditional Catholic philosophy and process philosophy. God bless!