That helped a lot. Going to your home page I found some error messages that tell us a lot about what's going on.
This error message:
In reply to:
Warning: include() [function.include]: URL file-access is disabled in the server configuration in /home/.muffin/urucka/desenhoporno.net/index.php on line 330
tells us that your scripts are trying to use unsupported options at Dreamhost. This is understandable as many servers allow these dangerous actions, but DH would rather disable the dangerous - especially when work arounds are available.
The wiki has this to say about "allow_url_fopen" (and why it's disabled on DH servers: http://wiki.dreamhost.com/index.php/Allow_url_fopen
Now, I know we haven't addressed your specific problem, but we have certainly determined that a bit of work is going to have be done to correct these issues. The php options that it this script is using are older and may be difficult to work around especially since development of mznews has been discontinued almost three years ago.
You might need to contact users/developers through sourceforge at http://sourceforge.net/projects/mzn2/ but it is looking pretty dead.
I don't want to fill in the install form since, if it worked, it would create your admin user. I am assuming it fails with an error. Could you show the error to us? (I'm not a big php guy, but there are some here and they'll jump in and correct me soon).
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