When namig category with russian letters we get nothing in the url for catname:
Same story happens with post categories, blog categories and all others.
The dirty solution is to name the category first with latin letters, then renaming it to what it means in Russian.
I guess this will happen in many other languages using non-latin alphabet.
To solve this once and forever I suggest to make a field named "URL-part" when creating a new category - same as when creating a new post - to be filled with latin catname and leave the original catname in native users' language.