Translation of vervierfachen

I am asking you to give me a reply as soon as possible so that we can proceed. Have you ever tested the new version? Many users are waiting for it, and are sending me lots of emails about it.
In plural there is no difference between the formal and the colloquial address form. Do you mean that you are using 3rd person singular form for the plural imperative? If so, I will change all entries so far.
Thank you for your feedback, I have little knowledge of the German language, and at the moment I have to use the dictionary a lot, and I read many articles from online newspapers and magazines.