hello and thank you for the first answer. Yes, perhaps it works. But I am not wondering if it works technically (Adobe put the files and a serial to that page, so you don't need activation anymore). I asked because of the legal concerns. As you write the serials are language specific I think that it is legally not possible. Perhaps Adobe reads this and thinks about its disclaimers on these pages and if my case is ok (regarding language swap).
I just want to make it right . In case of doubts I continue in EN or change to CS3.