Hey kk!
The paid version of the game is almost a month+ ahead of the free version. (It also helps support the continued development of the game!). Here's the schedule for the game:
The Alpha build of a new version is released at the start of each month. About a week later the Beta build is released. Then after another week the Early Access version is released. Then about a month later this version goes free and public. This is the Patreon schedule, so it gets released elsewhere a bit later on,
Currently, English is the primary language for the game. Russian is secondary and is being updated constantly. There used to be a fan translation for Spanish, but it hasn't been updated in years.
Hope this answers your question!