In an .htaccess file in the KBPublisher installation directory change and uncomment line:
php_value memory_limit
For example, if the desired limit is 32 MB, the following directive would be placed in the .htaccess:
php_value memory_limit "32M"
If you are on windows with IIS server .htaccess file will not work for you,
You should update this setting in php.ini file.