Administer > Settings > Flexicharge produces fatal error

Running Drupal 4.7.6
After upgrading from 4.7.x-2.1 to 4.7.x-3.0-rc1, and running update.php without error, went to administer > settings > flexicharge and got the following fatal error:

Fatal error: Cannot use string offset as an array in /hsphere/local/home/(redacted for privacy)/modules/system.module on line 748

Line 748 on my system module reads:

  $form['buttons']['submit'] = array('#type' => 'submit', '#value' => t('Save configuration') );

Essentially adding the submit reset buttons to a form.
The warnings logged read:

    * warning: Missing argument 2 for system_settings_form(), called in /hsphere/local/home/(redacted for privacy)/modules/ecommerce/contrib/flexicharge/flexicharge.module on line 70 and defined in /hsphere/local/home/(redacted for privacy)/modules/system.module on line 747.
    * warning: htmlspecialchars() expects parameter 1 to be string, array given in /hsphere/local/home/(redacted for privacy)/includes/bootstrap.inc on line 609.

Which is this:

function flexicharge_settings() {

  $form = array();
  $form['flexicharge']['taxonomy'] = array(
    '#type' => 'checkbox',
    '#title' => t('debug mode (watchdog)'),
    '#description' => t('Please choose a category list to be used by flexicharge.'),
    '#default_value' => variable_get('eyedrop_debugging_mode', FALSE),
  );
  return system_settings_form($form);
}

Which I think needs to look like this:

function flexicharge_settings() {

  $form = array();
  $form['flexicharge']['taxonomy'] = array(
    '#type' => 'checkbox',
    '#title' => t('debug mode (watchdog)'),
    '#description' => t('Please choose a category list to be used by flexicharge.'),
    '#default_value' => variable_get('eyedrop_debugging_mode', FALSE),
  );
//Add the form ID
  return system_settings_form('flexicharge_settings', $form);
}