Has the Categorical Imperative ever been denounced by the Catholic Church Lots of enlightenment thinking (particularly those leading towards too much collectivism or capitalism, freethought and rationalism) have been denounced by the Popes and the Saints and the Bishops and lots of other people,  but has Immanuel Kant ever been denounced?   I only took one introductory Philosophy class in college and the only system that I remotely took a fancy too was the Categorical Imperative. 

What I want to know is, in a broad sense, has it been found lacking in some way by the philosophical arm of the Catholic Church?  It seems to me a great way of refuting a number of the moral evils of the day (from littering to gay "marriage"), but is a Catholic justified in using it as a justification for anything?

I'd prefer any answer not go in to great detail about Kant himself; just the very basic nature of "something that is good for me, should be good for everyone".  Because it sounds to me like proto-personalism.
Kant's categorical imperative is very similar to the Protestant view that everyone is his or her own highest authority.

From the Catholic Encyclopedia article "Categorical Imperative":


  The merits of Kant's categorical imperative are said to consist in this: that it firmly establishes the reign of reason; elevates the dignity of man by subjecting in him sensibility to reason and making rational nature free, supreme, and independent; overcomes egoism by forbidding action from self-interest; and upholds morality by the highest authority. But the theist philosopher and the Christian theologian must needs take another view. Man is not an end in himself, but is essentially subordinate to God as his ultimate end and supreme good; nor is he autonomous, but is necessarily subject to God as his supreme Lord and lawgiver. Man, conceived as a law unto himself and an end in himself, is emancipated from God as his master and separated from Him as his supreme good; conceived, moreover, as autonomous and independent of any higher authority, he is deified. This is not building up true and lofty morality, but is its complete overthrow; for the basis of morality is God as the ultimate end, highest good, and supreme lawgiver. Kant utterly ignores the nature of both intellect and will. Human reason does not enact the moral law, but only voices and proclaims it as the enactment of a higher power above man, and it is not from the proclaiming voice that the law derives its binding force, but from the majesty above that intimates it to us through our conscience.