Paymill Undefined index notice on WP 3.6-beta4

That one is fixed but additional errors occurred on update.

[ Moderator note: please wrap code in backticks or use the code button. ]

DESCRIBE wp_paymill_clients;
require_once('wp-admin/admin.php'), require_once('wp-load.php'), require_once('wp-config.php'), require_once('wp-settings.php'), include_once('/plugins/paymill/paymill.php'), paymill_install, dbDelta #1 (0.6ms)
SHOW INDEX FROM wp_paymill_clients;
require_once('wp-admin/admin.php'), require_once('wp-load.php'), require_once('wp-config.php'), require_once('wp-settings.php'), include_once('/plugins/paymill/paymill.php'), paymill_install, dbDelta #2 (0.1ms)
DESCRIBE wp_paymill_transactions;
require_once('wp-admin/admin.php'), require_once('wp-load.php'), require_once('wp-config.php'), require_once('wp-settings.php'), include_once('/plugins/paymill/paymill.php'), paymill_install, dbDelta #3 (0.4ms)
SHOW INDEX FROM wp_paymill_transactions;
require_once('wp-admin/admin.php'), require_once('wp-load.php'), require_once('wp-config.php'), require_once('wp-settings.php'), include_once('/plugins/paymill/paymill.php'), paymill_install, dbDelta #4 (0.1ms)
ALTER TABLE wp_paymill_clients ADD PRIMARY KEY ( paymill_client_id)
require_once('wp-admin/admin.php'), require_once('wp-load.php'), require_once('wp-config.php'), require_once('wp-settings.php'), include_once('/plugins/paymill/paymill.php'), paymill_install, dbDelta #5 (35.7ms)
ALTER TABLE wp_paymill_clients ADD KEY paymill_client_email ( paymill_client_email)
require_once('wp-admin/admin.php'), require_once('wp-load.php'), require_once('wp-config.php'), require_once('wp-settings.php'), include_once('/plugins/paymill/paymill.php'), paymill_install, dbDelta #6 (0.1ms)
ALTER TABLE wp_paymill_transactions ADD PRIMARY KEY ( paymill_transaction_id)
require_once('wp-admin/admin.php'), require_once('wp-load.php'), require_once('wp-config.php'), require_once('wp-settings.php'), include_once('/plugins/paymill/paymill.php'), paymill_install, dbDelta #7 (0.1ms)
ALTER TABLE wp_paymill_transactions ADD KEY paymill_payment_id ( paymill_payment_id)
require_once('wp-admin/admin.php'), require_once('wp-load.php'), require_once('wp-config.php'), require_once('wp-settings.php'), include_once('/plugins/paymill/paymill.php'), paymill_install, dbDelta #8 (0.1ms)
UPDATE <code>wp_options</code> SET <code>option_value</code> = '1201' WHERE <code>option_name</code> = 'paymill_db_version'
require_once('wp-admin/admin.php'), require_once('wp-load.php'), require_once('wp-config.php'), require_once('wp-settings.php'), include_once('/plugins/paymill/paymill.php'), paymill_install, update_option #9 (0.1ms)
SELECT * FROM wp_users WHERE user_login = 'ip'
require_once('wp-admin/admin.php'), require_once('wp-load.php'), require_once('wp-config.php'), require_once('wp-settings.php'), WP->init, wp_get_current_user, get_currentuserinfo, wp_validate_auth_cookie, get_user_by, WP_User::get_data_by #10 (0.2ms)
SELECT user_id, meta_key, meta_value FROM wp_usermeta WHERE user_id IN (2)
require_once('wp-admin/admin.php'), require_once('wp-load.php'), require_once('wp-config.php'), require_once('wp-settings.php'), WP->init, wp_get_current_user, get_currentuserinfo, wp_validate_auth_cookie, get_user_by, WP_User->init, WP_User->for_blog, WP_User->_init_caps, get_user_meta, get_metadata, update_meta_cache #11 (0.1ms)
SELECT option_value FROM wp_options WHERE option_name = 'widget_pages' LIMIT 1
require_once('wp-admin/admin.php'), require_once('wp-load.php'), require_once('wp-config.php'), require_once('wp-settings.php'), do_action('init'), call_user_func_array, wp_widgets_init, do_action('widgets_init'), call_user_func_array, WP_Widget_Factory->_register_widgets, WP_Widget->_register, WP_Widget->get_settings, get_option #12 (0.1ms)
SELECT option_value FROM wp_options WHERE option_name = 'widget_calendar' LIMIT 1
require_once('wp-admin/admin.php'), require_once('wp-load.php'), require_once('wp-config.php'), require_once('wp-settings.php'), do_action('init'), call_user_func_array, wp_widgets_init, do_action('widgets_init'), call_user_func_array, WP_Widget_Factory->_register_widgets, WP_Widget->_register, WP_Widget->get_settings, get_option #13 (0.1ms)
SELECT option_value FROM wp_options WHERE option_name = 'widget_tag_cloud' LIMIT 1
require_once('wp-admin/admin.php'), require_once('wp-load.php'), require_once('wp-config.php'), require_once('wp-settings.php'), do_action('init'), call_user_func_array, wp_widgets_init, do_action('widgets_init'), call_user_func_array, WP_Widget_Factory->_register_widgets, WP_Widget->_register, WP_Widget->get_settings, get_option #14 (0.1ms)
SELECT option_value FROM wp_options WHERE option_name = 'widget_nav_menu' LIMIT 1
require_once('wp-admin/admin.php'), require_once('wp-load.php'), require_once('wp-config.php'), require_once('wp-settings.php'), do_action('init'), call_user_func_array, wp_widgets_init, do_action('widgets_init'), call_user_func_array, WP_Widget_Factory->_register_widgets, WP_Widget->_register, WP_Widget->get_settings, get_option #15 (0.1ms)
SELECT option_value FROM wp_options WHERE option_name = 'widget_browserid_widget' LIMIT 1
require_once('wp-admin/admin.php'), require_once('wp-load.php'), require_once('wp-config.php'), require_once('wp-settings.php'), do_action('init'), call_user_func_array, wp_widgets_init, do_action('widgets_init'), call_user_func_array, WP_Widget_Factory->_register_widgets, WP_Widget->_register, WP_Widget->get_settings, get_option #16 (0.1ms)
SELECT option_value FROM wp_options WHERE option_name = '_site_transient_update_plugins' LIMIT 1
require_once('wp-admin/admin.php'), require('wp-admin/menu.php'), wp_get_update_data, get_site_transient, get_site_option, get_option #17 (0.1ms)
SELECT option_value FROM wp_options WHERE option_name = 'dismissed_update_core' LIMIT 1
require_once('wp-admin/admin.php'), require('wp-admin/menu.php'), wp_get_update_data, get_core_updates, get_site_option, get_option #18 (0.1ms)
SELECT comment_approved, COUNT( * ) AS num_comments FROM wp_comments GROUP BY comment_approved
require_once('wp-admin/admin.php'), require('wp-admin/menu.php'), wp_count_comments #19 (0.1ms)
INSERT INTO <code>wp_options</code> (<code>option_name</code>, <code>option_value</code>, <code>autoload</code>) VALUES ('_site_transient_update_plugins', 'O:8:\"stdClass\":1:{s:12:\"last_checked\";i:1374565605;}', 'yes') ON DUPLICATE KEY UPDATE <code>option_name</code> = VALUES(<code>option_name</code>), <code>option_value</code> = VALUES(<code>option_value</code>), <code>autoload</code> = VALUES(<code>autoload</code>)
require_once('wp-admin/admin.php'), do_action('admin_init'), call_user_func_array, _maybe_update_plugins, wp_update_plugins, set_site_transient, add_site_option, add_option #20 (0.1ms)
UPDATE <code>wp_options</code> SET <code>option_value</code> = 'O:8:\"stdClass\":2:{s:12:\"last_checked\";i:1374565605;s:8:\"response\";a:0:{}}' WHERE <code>option_name</code> = '_site_transient_update_plugins'
require_once('wp-admin/admin.php'), do_action('admin_init'), call_user_func_array, _maybe_update_plugins, wp_update_plugins, set_site_transient, update_site_option, update_option #21 (0.2ms)
UPDATE <code>wp_options</code> SET <code>option_value</code> = 'O:8:\"stdClass\":3:{s:12:\"last_checked\";i:1374565606;s:7:\"checked\";a:13:{s:19:\"akismet/akismet.php\";s:5:\"2.5.8\";s:41:\"authy-two-factor-authentication/authy.php\";s:3:\"2.3\";s:23:\"debug-bar/debug-bar.php\";s:5:\"0.8.1\";s:41:\"debug-bar-extender/debug-bar-extender.php\";s:3:\"0.5\";s:43:\"molekula-weatherapp/molekula-weatherapp.php\";s:3:\"0.1\";s:27:\"weather-one/weather-one.php\";s:3:\"0.2\";s:23:\"browserid/browserid.php\";s:4:\"0.44\";s:11:\"mp6/mp6.php\";s:3:\"1.8\";s:19:\"paymill/paymill.php\";s:5:\"1.2.1\";s:25:\"sucuri-scanner/sucuri.php\";s:5:\"1.2.1\";s:40:\"wordpress-beta-tester/wp-beta-tester.php\";s:4:\"0.96\";s:29:\"wunderground/wunderground.php\";s:7:\"1.2.5.1\";s:35:\"youtube-channel/youtube-channel.php\";s:5:\"1.5.1\";}s:8:\"response\";a:0:{}}' WHERE <code>option_name</code> = '_site_transient_update_plugins'
require_once('wp-admin/admin.php'), do_action('load-plugins.php'), call_user_func_array, wp_update_plugins, set_site_transient, update_site_option, update_option #22 (0.3ms)
SELECT option_value FROM wp_options WHERE option_name = '_transient_plugin_slugs' LIMIT 1
WP_Plugins_List_Table->prepare_items, set_transient, get_option #23 (0.1ms)
SELECT option_value FROM wp_options WHERE option_name = '_transient_timeout_plugin_slugs' LIMIT 1
WP_Plugins_List_Table->prepare_items, set_transient, update_option, get_option #24 (0.1ms)
UPDATE <code>wp_options</code> SET <code>option_value</code> = '1374652007' WHERE <code>option_name</code> = '_transient_timeout_plugin_slugs'
WP_Plugins_List_Table->prepare_items, set_transient, update_option #25 (0.1ms)
UPDATE <code>wp_options</code> SET <code>option_value</code> = 'O:8:\"stdClass\":3:{s:7:\"updates\";a:1:{i:0;O:8:\"stdClass\":9:{s:8:\"response\";s:11:\"development\";s:8:\"download\";s:56:\"http://wordpress.org/nightly-builds/wordpress-latest.zip\";s:6:\"locale\";s:5:\"en_US\";s:8:\"packages\";O:8:\"stdClass\":4:{s:4:\"full\";s:56:\"http://wordpress.org/nightly-builds/wordpress-latest.zip\";s:10:\"no_content\";b:0;s:11:\"new_bundled\";b:0;s:7:\"partial\";b:0;}s:7:\"current\";s:5:\"3.5.2\";s:11:\"php_version\";s:5:\"5.2.4\";s:13:\"mysql_version\";s:3:\"5.0\";s:11:\"new_bundled\";s:3:\"3.5\";s:15:\"partial_version\";s:0:\"\";}}s:12:\"last_checked\";i:0;s:15:\"version_checked\";s:13:\"3.6-RC1-24757\";}' WHERE <code>option_name</code> = '_site_transient_update_core'
require_once('wp-admin/admin-header.php'), do_action('admin_head-plugins.php'), call_user_func_array, wp_beta_tester->action_admin_head_plugins_php, set_site_transient, update_site_option, update_option #26 (0.1ms)
SELECT COUNT(NULLIF(<code>meta_value</code> LIKE '%"administrator"%', false)), COUNT(NULLIF(<code>meta_value</code> LIKE '%"editor"%', false)), COUNT(NULLIF(<code>meta_value</code> LIKE '%"author"%', false)), COUNT(NULLIF(<code>meta_value</code> LIKE '%"contributor"%', false)), COUNT(NULLIF(<code>meta_value</code> LIKE '%"subscriber"%', false)), COUNT(*) FROM wp_usermeta WHERE meta_key = 'wp_capabilities'
require_once('wp-admin/admin-header.php'), do_action('admin_head-plugins.php'), call_user_func_array, wp_beta_tester->action_admin_head_plugins_php, wp_version_check, count_users #27 (0.2ms)
UPDATE <code>wp_options</code> SET <code>option_value</code> = 'O:8:\"stdClass\":3:{s:7:\"updates\";a:1:{i:0;O:8:\"stdClass\":9:{s:8:\"response\";s:11:\"development\";s:8:\"download\";s:56:\"http://wordpress.org/nightly-builds/wordpress-latest.zip\";s:6:\"locale\";s:5:\"en_US\";s:8:\"packages\";O:8:\"stdClass\":4:{s:4:\"full\";s:56:\"http://wordpress.org/nightly-builds/wordpress-latest.zip\";s:10:\"no_content\";b:0;s:11:\"new_bundled\";b:0;s:7:\"partial\";b:0;}s:7:\"current\";s:5:\"3.5.2\";s:11:\"php_version\";s:5:\"5.2.4\";s:13:\"mysql_version\";s:3:\"5.0\";s:11:\"new_bundled\";s:3:\"3.5\";s:15:\"partial_version\";s:0:\"\";}}s:12:\"last_checked\";i:1374565607;s:15:\"version_checked\";s:13:\"3.6-RC1-24757\";}' WHERE <code>option_name</code> = '_site_transient_update_core'
require_once('wp-admin/admin-header.php'), do_action('admin_head-plugins.php'), call_user_func_array, wp_beta_tester->action_admin_head_plugins_php, wp_version_check, set_site_transient, update_site_option, update_option #28 (0.3ms)

<strong>Database Errors</strong>

ALTER TABLE wp_paymill_clients ADD PRIMARY KEY ( paymill_client_id)
Multiple primary key defined
ALTER TABLE wp_paymill_clients ADD KEY paymill_client_email ( paymill_client_email)
Duplicate key name 'paymill_client_email'
ALTER TABLE wp_paymill_transactions ADD PRIMARY KEY ( paymill_transaction_id)
Multiple primary key defined
ALTER TABLE wp_paymill_transactions ADD KEY paymill_payment_id ( paymill_payment_id)
Duplicate key name 'paymill_payment_id'
</blockquote>
And now we have 5 Notices in debugger: 

<blockquote>NOTICE: wp-content/plugins/paymill/paymill.php:122 - Undefined index: currency
NOTICE: wp-content/plugins/paymill/lib/integration/pay_button.inc.php:106 - Undefined index: paymill_pay_button_order
NOTICE: wp-content/plugins/paymill/lib/tpl/pay_button.php:16 - Undefined index: currency
NOTICE: wp-content/plugins/paymill/lib/tpl/checkout_form.php:24 - Undefined index: elv
NOTICE: wp-content/plugins/paymill/lib/tpl/checkout_form.php:58 - Undefined variable: cart_total