The manual is probablly outdated considering all of the paatches that have been put into the game.
I still have my original manual. It would be a bit dated, but not OUTdated, especially if it is available in his milk tongue. You mainly want a manual to get you through basic mechanics, screen tools, conceptual relationships. None of that has changed.
What's changed is things like exact racial bonus values, point values or bonus valoues of some buildings, behind-the-scenes combat calculations that the manual didn't explain in detail anyway.
But how to assign tiles on a planet, or how to manipulate the sliders, or how to select and move ships, or how to design ships has not changed. He can suplement from the English-language DA .pdf, and from the wiki, and from this forum, once he has a grounding in the mechanics.
drrider