Good question. But, unfortunately ther is no simple way. It will be necessary to hack programs below.
About 2:
You can override language phrase of Q2A core by using qa-lang/custom folder. Refer page below. http://www.question2answer.org/translate.php >>> "Customizing selected URLs or phrases"
Create a qa-lang-*.php file in Q2A's qa-lang/custom directory, with the same name as the file that you found in the previous step, and paste in the following code:
In addition, my plugin may be helpful for you.
Good luck.
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