RE: the German ancestors of Grace Kelly through her mother, Margaret Katherine Majer/Maier, daughter of Carl Majer and Margaretha Berg: I have searched again through my files and have located the three publications called "Genealogie" from Jan-Fe. 1964; March 1965; and April 1967. These journals are published in the German language. However, aside from a bit of narrative at the beginning which speaks about the religious affiliations [Grace's grandmother's ancestors were mostly Catholic, but because this area was geographically overrun many times during the 30 Years' War, there were and still are evangelical churches in the area - and some of the Berg family ancestors were evangelical], the lineages are easy to interpret.
Regarding her grandfather, Carl Majer, his ancestors were the opposite from the Berg family, in that they were predominantly Protestant being Evangelical, Luthran, and even a few Mennonites as well as some Catholics. So it makes for an interesting mix.
The first publication was Heft 1, 13. Jahrgang, Jan.-Febr. 1964 [Booklet 1, 13th Year]. Pages 1-10. With Grace Kelly as Number 1, the ancestry goes up through 12 generations. The 12th generation listed were entirely those from the Majer side of the family. The author was C. Frederick Kaufholz. So, this listing includes ancestors of both grandparents.
The second publication was Heft 3, 14. Jahrgang, March 1895. Pages 454 to 459 are "More about the Ancestor lists of Princess Grace Patricia of Monaco, nee Kelly" [translated title] by H. W. Eben-Ebenau. This is all ancestors of her grandfather, Carl Majer. Beginning on page 459 through page 463 are three separate listings of Carl Majer's ancestors from Wuerttemberg and Silesia. [three different contributors]
The third publication was Heft 4, 16. Jahrgang, April 1967. Included in the narrative are lovely pictures of Grace, her mother, Margaret Kelly, nee Majer, and her grandmother, Margaretha Majer, nee Berg. Pages 673-693 are "Further News About the Ancestors of Princess Grace Patricia of Monaco, nee Kelly", and concerns the ancestors on the Majer side. There are several contributors, as the listings are in sections based on geography. Pages 694 to 702 are by Ernst Loeslein and covers the "Ancestry of Margaretha Berg [Grace's maternal Grandmother], born 1870. It covers 12 generations which indicates it has additional data not included in the 1964 publication.
I hope this is helpful. You may contact me at firstname.lastname@example.org