Problem Адрес профиля укотротить

Try to explain better what you need to do.....

Open ../application/modules/User/Form/Signup/Account.php

and find code:

PHP:

// Element: username
    if( $settings->getSetting('user.signup.username', 1) > 0 ) {
      $description = Zend_Registry::get('Zend_Translate')
          ->_('This will be the end of your profile link, for example: <br /> ' .
              '<span id="profile_address">http://%s</span>');
      $description = sprintf($description, $_SERVER['HTTP_HOST']
          . Zend_Controller_Front::getInstance()->getRouter()
          ->assemble(array('id' => 'yourname'), 'user_profile'));

      $this->addElement('Text', 'username', array(
        'label' => 'Profile Address',
        'description' => $description,
        'required' => true,
        'allowEmpty' => false,
        'validators' => array(
          array('NotEmpty', true),
          array('Alnum', true),
          array('StringLength', true, array(4, 64)),
          array('Regex', true, array('/^[a-z][a-z0-9]*$/i')),
          array('Db_NoRecordExists', true, array(Engine_Db_Table::getTablePrefix() . 'users', 'username'))
        ),

There you have part of code who allow minimum and maximum characters for User names

PHP:

array('StringLength', true, array(4, 64)),

These two numbers are:
4 - minimum allowed characters
64 - maximum allowed characters

change it on what you liked to be...