The Cyrillic characters in Yawerty.txt.in are double-UTF8-encoded.
For example, it contains
STATUS_PROMPT = Я
but that line should be
STATUS_PROMPT = Я
It appears to have been broken with this changeset:
http://scim.svn.sourceforge.net/viewvc/scim/scim-tables/trunk/tables/ru/Yawerty.txt.in?r1=93&r2=262
Tz-Huan, is the development for scim-tables still happening in sf.net?