Q: I've installed xruskb and it works, but I don't see russian letters but
   see accented latin letters instead.
A: You have to tune your applications to use proper russian fonts.
   See Cyrillic-HOWTO at ftp://metalab.unc.edu/pub/Linux/docs/HOWTO/unmaintained/
   (it is not only for linux)

Q: I cannot input russian letters.
A: There can be several reasons. If you use *-cyr key map, then it is
   important to have a recent version of XFree86 and proper localization, that
   is LC_CTYPE=ru_RU.KOI8-R, and XFree86 should be able to recognize the
   charset. On some versions of glibc is is needed to add a locale alias to
   /usr/X11R6/lib/X11/locale/locale.alias, a line containing

      ru_RU.koi8r    ru_RU.KOI8-R

   If you use *-koi8 key maps (or different encoding), then sometimes it is
   important NOT to have a localization. It is a hack method anyway. See also
   Cyrillic-HOWTO on how to tune bash.

Q: Which keyboard map should I use?
A: If you have recent version of XFree86 and have proper localization
   (i.e. set LANG or LC_CTYPE to something like ru_RU.KOI8-R), use
   jcuken-cyr. Otherwise, try jcuken-koi8 or different encoding.
   If your keyboard lacks russian marking, you may prefer yawerty-*
   keymaps which have semi-phonetic correspondence between latin and
   russian letters. Experiment and find out what works for you better.

Q: Why xrus is needed when there is XKB extension?
A: First, there are X11R5 servers, which don't have XKB extension. Second,
   xrus works fine for many people and it is easy to set up, and it does
   not conflict with XKB.