Help needed to start with Piwik on Debian (no replies)

Hello,

I am struggling a little to start with Piwik on Debian Wheezy.
I have installed the Debian package piwik 2.2.0-1 according to:
http://debian.piwik.org/

After that I edited the file /etc/piwik/apache.cong to uncomment this line:

Alias /piwik /usr/share/piwik

And then configured MySQL, I restarted Apache and went to this URL:
http://example.com/piwik

I had the following problems:

1. the URL http://example.com/piwik doesn't work, I had to use explicitely http://example.com/piwik/index.php
2. the configuration went without any problem except that it seems that I haven't got any CSS or Javascript (the configuration pages were just text and buttong)
3. Now I got a login/password page at http://example.com/piwik/index.php, but my login/password doesn't work, the button "Lost password ?" doesn't do anything when pressed and it seems again that I don't have any CSS
4. When using the Firefox Developer tool I can see the following error messages:
   

     Use of getUserData() or setUserData() is deprecated. Use WeakMap or element.dataset instead.  ReferenceError: $ is not defined @ http://example.com/piwik/index.php:33  ReferenceError: $ is not defined @ http://example.com/piwik/index.php:45  

5. I look at the forum and I saw this post about CSS not workong on Piwik 2.2: [forum.piwik.org]
6. However I haven't been able to have any log. I modified /etc/piwik/global.ini.php to add:
   

     [log]  log_writers[] = file  log_level = VERBOSE  logger_file_path = tmp/piwik.log

   I restarted apache but no file is ever created in /tmp and so I cannot see any logs

I am feeling a bit lost in all these problems just at the very beginning of installation. Can someone give me a hand to get started ?

Thanks in advance !