Replaygain not working at all?

Hello, first let me thank you for this superb application - works great.

After installing and runing the station for some time, we found there is a need for some volume normalisation and after some googling and reading docs I’ve read about Replaygain function. It should work that it tags the files when importing, if I understand correctly. But when looking in track library, there is not even one file, be it tagged or untagged mp3 or flac, that has it set and I cound not find a way to edit it manualy from Libretime gui.
I’ve tried if there is replaygain installed and it works - the system knowns the command. It’s clean install of ubuntu 18.04, libretime downloaded from repo about two weeks ago version 04ea316ca according to /root/libretime/version .
Is this disabled or am I doing something wrong? I would like also to know if there is some easy way to hook some sound postprocessing (limiter/normaliser) on output stream…

Found multiple
[replaygain_analyzer] [WARNI] ‘NoneType’ object has no attribute ‘group’
warnings in airtime_analyzer.log

Found the fix - replaygain returned deprecation warning about ubuntu 18.04 and unsupported future versions of python and replaygain analyzer could not parse the output correctly.

What I did is pretty dirty, but it works -
I disabled the warning in usr/local/lib/python3.6/dist-packages/pkg?resources/ around line 112 - i put in comments all content of def parse_version(v).

It would be nice to have some tool to reanalyse all imported tracks.