Thank you. I updated the Czech language file in the repository.
Regarding the issues in the English file:
db_not_writeable and the new database_not_writable (note: database
instead of db) has a very similar key but is for a different kind of
issue. The old one is in case the database cannot be created because the
directory is not writeable. This is a severe problem. The new one is in
case the database exists but is not writeable, i.e. can only be viewed
but not written to. This is a very different case.
Sure, the names for the keys (esp. the old one) may not be chosen well. Bur we really need both.
2. No, partial indexes are really indexes over a subset of rows, not columns. See: https://www.sqlite.org/partialindex.html