I wrote concerning my way of keyboarding Russian Cyrillic
on a Mac physical Keyboard for latin script:

 > To get the 33 letters of the Russian alphabet one types
 > respectively:
 >
 >      a b v g d e 'o 'z z i j k l m n o p r
 >      s t u f x 't 'c w 'w q y h 'e 'u 'a    
 >
 > The Russian Cyrillic letters \cyra, \cyrb, \cyrv, ... ,
 > \cyrya appear on the screen.  The eight "doublets" 'o 'z 't
 > 'c 'e 'u 'a  each produce *one* Cyrillic character via the
 > Mac's official "dead-key" mechanism --- which all West
 > Europeans employ in typing some or all accented characters;
 > the "Norwegian-Russian" KCHR resource configures this
 > mechanism.

     I should have also mentioned a (compatible) alternative to
this "dead-key" typing of the eight Russian characters accessed
above using  dead-key ' . Instead of typing  'a  (two
successive keystrokes) to get the Cyrillic glyph \cyrya on
screen, one can type

          Alt  a

i.e. lowercase keystroke  a  while the modifier key  Alt  is
depressed.  Sililarly for the other 7.  Some typists dislike
dead-keys; here is a reasonable alternative with equal mnemonic
value.

Cheers

Laurent S.