Oleinu - "Shehem Mishtachavim" etc.

As you assumed, these words were censored. We have evidence that in Ashkenaz these words were said as long as they were remembered.

Michael FRBSH

I would like to add, that in Divrei Kehillos pg 168, when talking about Oleinu Leshabe'ach of Rosh Hashono (Musaf), he mentions that the tzibbur says quietly Shehem untill Lo Youshia. So it is clear that this minhag was still kept in his days (year 5579). It is also quite clear from the way Oleinu is mentioned to be said in Divrei Kehillos (until after kechol Hamounom quietly, and then loud again from Shehoo Nouteh Shomayim) that these words were said too and therefore purposely everything was said quietly. And this was of saying Oleinu can be still heard in Chazzan Weis's cassettes.

Michael

The old Minhag is Shelou Osani Goi. This minhag was kept in Frankfurt until today, therefore in Washington Heights and in KAYJ this is the nusach said.
The Censors were not happy with Goi, so they changed it to Shelou Osani Yishmoel or Akum or Kusi (or She'osani Yisro'el). Shelou Osani Nochri came as a compromise.

Michael FRBSH

p.s. Machon Moreshes Ashkenaz (MMA) is working on a new Siddur, without the censors changes.

The reason we close the ark is because we do not want to mention the idols of the Goyyim next to the Aron Kodesh. This applies mostly to Shehem Mishtachavim Lohevel Vorik.

Michael FRBSH