First of all that is a great debug tool! Thanks. Furthermore, it make use of an old friend of mine: krumo! I was really happy when, enabling the plugin, I saw "Cannot redeclare krumo class". Oh yeah.
But please, correct a deprecated parameter in your code, on line 68:
add_options_page('WP-Devel Options', 'WP-Devel', 8, __FILE__, 'wds_dts_options');
the use of user level instead of the role name is deprecated, so I've changed line 68 to
add_options_page('WP-Devel Options', 'WP-Devel', 'administrator', __FILE__, 'wds_dts_options');
Please include this fix in your future release of wp-devel.