Well, here's what I came up after some listening and thinking.

There definitely are some additional sounds between consonants and after the last consonant in a word, especially when the consonants are voiced.

The question is, whether to treat them as phonemes or just as transition noises.

Standard Russian, as taught in Soviet schools in '70s, obviously didn't treat them as phonemes. Many individuals, as well as many dialects, do (e. g. in folk songs you can run into something like "в горнице свечи тепылютыся" with those ы-like noises sung just like any vowel).

So, it's perfectly all right to let some very reducted semi-vowel appear between consonants. Many native speakers just won't hear it, and others won't mind. Just see to it that it's really short, faint, and absolutely reducted.

Just my .02 of course.