Can I download a older version of opera in the meantime?
Yep!, You most certainly can, knock yourself out.
ftp://ftp.opera.com/pub/opera/win/
EDIT: You may want to try 12.14 as it seems to be more stable, more site compatible than the latest 12.16. And it allows you the ability to change the default search engine to anything you wish, unlike 12.16 which only allows any of the provided search engines to be made the default.
But you are free to choose whichever version of Opera you wish to use. Obviously taking security risks and vulnerabilities into consideration.