I need help with this htaccess rewrite rule

Code:

---

RewriteEngine On
RewriteRule ^http:\/\/(www\.)?xn--zhq692d06i\.net(.*)$ http://linksku.com/idn/56/viewforum.php?f=7&$2

---

I have a domain xn--zhq692d06i.net and linksku.com. The files for xn--zhq692d06i.net are actually at http://linksku.com/idn/adirectory, my host configured the server to make it work. However, I want to make xn--zhq692d06i.net use the files from http://linksku.com/idn/56/

For example, if a users goes to http://xn--zhq692d06i.net/t=2, I want http://linksku.com/idn/56/viewforum.php?f=7&t=2 to be displayed.

Another problem. When I was playing around with htaccess to try and get this working, I noticed that sometimes the rewriterule redirects the page, instead of simple loading a different file, while keeping the URL as-is. How can I prevent it from redirecting?

Nevermind, I think I misunderstood everything about htaccess when I asked this question.

Now I have a new question, how does WordPress maintain the URL as a "pretty URL" even though a different file is loaded with htaccess? I want to do something similar.