It gives this message:
Fatal error: Undefined class constant 'WPDOMAIN' in /home/********/public_html/wp-content/plugins/wpmandrill/stats.php on line 5
I'v looked around and I've found that there are many references to WPDOMAIN inside stats.php file. But it's not defined in wpMandrill class in wpmandrill.php.
Looking at an older version of wpmandrill.php, I saw that WPDOMAIN was indeed defined as 'wpmandrill'. But in current 1.24 version is not, since uses 'wpmandrill' hardcoded where before was the constant. stats.php doesn't reflect that change.
I added WPDOMAIN as a constant in wpMandrill class, like in the old version, and now the statistics page works. But this should be fixed.