In addition to
adicoto's earlier findings:
all further windows/messages of codec manager (meanwhile tried) also untranslated.
E.g.
Warning
Old version of ..... was found on system.
It is strongly recommended to uninstall this version.
BS.Player codec manager
Available codecs
Name - Status - Version available
Information/Description - Licence - Website
Uninstall selected - Refresh - Install selected
Information
The following filters will be installed:
...
Do you want to continue?
(and some other message at the end which I forgot to note down)