Hello Jorge,
exactly, do you have the same problem?
Please note, as far as I know you need the DB-Size and create the data-files, which are having the same size like the source-db is having (including the unreserved space).
I also found a way to reduce the data-files and sizes after the migration, to not waste to much space.
(e.g., a live system is much faster gowinger and therefore you have much more db-files reserved, what you may don't need for the q-system).
Kind regards