It was pointed out to me by David Bronson my learning partner, that the censor caused great problems because now we never know when the Gemara refers to "Akum", [עכו''ם ר''ת עובד כוכבים ומזלות] "goy", "Kuti" כותי etc., to whom are they referring to? The censor by changing things around: "goy" to "akum" and visa verse along with many changes, now  we can never know. [Though I have found that it is possible to figure it out from the context.]

There are differences between these categories. For example "goy" refers to a gentile. "Akum" refers to an idolater who can be Jew or gentile. What makes an "Akum" into an akum is the fact of doing idolatry, not if they are Jewish or not. Kuti is a Samarian. So now when the Gemara says one category we never know if perhaps the original Gemara had a different category.

[So "Akum" will not be referring to a Muslim, and neither to a Christian to many Rishonim opinions like the Meiri and Abravanel, and Tosphot in tractate Avoda Zara. [That Tosphot deals with the famous issue of "joining" שיתוף which should be easy to find, but I admit I forgot the page number.]

One result of this ambiguity is that some people think when the gemara refers to idolaters that it means gentiles. That is a commonplace mistake. Idolater means an idolater. --that is one who does idolatry.