diff --git a/TODO b/TODO
index 99affff..b79437c 100755
--- a/TODO
+++ b/TODO
@@ -1,4 +1,3 @@
-* Check database creation in install.php
 * Don't display the whole balance table if not admin
 * Notifications by e-mail for users
 
diff --git a/index.php b/index.php
index 41a03ad..e7ec1a7 100644
--- a/index.php
+++ b/index.php
@@ -11,7 +11,7 @@
         'template_error'=>array('fr'=>'Template non disponible.', 'en'=>'Template not available.'),
         'unauthorized'=>array('fr'=>'Vous n\'avez pas le droit de faire cette action.', 'en'=>'You are not authorized to do that.'),
         'no_users'=>array('fr'=>'Vous devez ajouter au moins un autre utilisateur.', 'en'=>'You must add at least one more user beside you.'),
-        'what_unknown,'=>array('fr'=>'Vous devez renseigner un objet pour la dépense.', 'en'=>'You must add something to describe this invoice in "what" field.'),
+        'what_unknown'=>array('fr'=>'Vous devez renseigner un objet pour la dépense.', 'en'=>'You must add something to describe this invoice in "what" field.'),
         'incorrect_amount'=>array('fr'=>'Montant incorrect ou nul.', 'en'=>'Incorrect amount or amount is zero.'),
         'email_invalid'=>array('fr'=>'L\'adresse e-mail est invalide.', 'en'=>'Incorrect e-mail address.')
     );
@@ -540,9 +540,9 @@
             $tpl->assign('what_post', (!empty($what) ? htmlspecialchars($what) : ''));
             $tpl->assign('users', secureDisplay($users_list));
 
-            if(empty($_POST['what']))
+            if(isset($_POST['what']) && empty($_POST['what']))
                 $tpl->assign('error', $errors['what_unknown'][LANG]);
-            if((float) $_POST['amount'] == 0)
+            if(!empty($_POST['amount']) && (float) $_POST['amount'] == 0)
                 $tpl->assign('error', $errors['incorrect_amount'][LANG]);
 
             $tpl->assign('users_in', (!empty($users_in) ? $users_in : array()));
diff --git a/install.php b/install.php
index 365a71d..351b9d9 100644
--- a/install.php
+++ b/install.php
@@ -29,7 +29,7 @@
             $db = new PDO('mysql:host='.$mysql_host.';dbname='.$mysql_db, $mysql_login, $mysql_password);
 
             //Create table "Users"
-            $db->query('CREATE TABLE IF NOT EXISTS '.$mysql_prefix.'Users (id INT(11) NOT NULL AUTO_INCREMENT PRIMARY KEY, login VARCHAR(255), display_name VARCHAR(255), password VARCHAR(130), admin TINYINT(1), json_token VARCHAR(32)) DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci');
+            $db->query('CREATE TABLE IF NOT EXISTS '.$mysql_prefix.'Users (id INT(11) NOT NULL AUTO_INCREMENT PRIMARY KEY, login VARCHAR(255), email VARCHAR(255), display_name VARCHAR(255), password VARCHAR(130), admin TINYINT(1), json_token VARCHAR(32), notifications TINYINT(1)) DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci');
 
             //Create table "Invoices"
             $db->query('CREATE TABLE IF NOT EXISTS '.$mysql_prefix.'Invoices (id INT(11) NOT NULL AUTO_INCREMENT PRIMARY KEY, date DATETIME, buyer INT(11), amount INT(11), what TEXT) DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci');
@@ -41,7 +41,7 @@
             $db->query('CREATE TABLE IF NOT EXISTS '.$mysql_prefix.'Paybacks (id INT(11) NOT NULL AUTO_INCREMENT PRIMARY KEY, date DATETIME, invoice_id INT(11), KEY invoice_id (invoice_id), amount INT(11), from_user INT(11), to_user INT(11)) DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci');
 
             // Create table "GlobalPaybacks"
-            $db->query('CREATE TABLE IF NOT EXISTS '.$mysql_prefix.'GlobalPaybacks (id INT(11) NOT NULL AUTO_INCREMENT PRIMARY KEY, date DATETIME) DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci');
+            $db->query('CREATE TABLE IF NOT EXISTS '.$mysql_prefix.'GlobalPaybacks (id INT(11) NOT NULL AUTO_INCREMENT PRIMARY KEY, date DATETIME, closed TINYINT(1)) DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci');
 
             // Create table "Users_in_GlobalPaybacks"
             $db->query('CREATE TABLE IF NOT EXISTS '.$mysql_prefix.'Users_in_GlobalPaybacks (global_payback_id INT(11) NOT NULL, KEY global_payback_id (global_payback_id), user1_id INT(11), user2_id INT(11), amount INT(11)) DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci');
diff --git a/tpl/default_en/css/style.css b/tpl/default_en/css/style.css
index a6d6d2d..5cfcb69 100644
--- a/tpl/default_en/css/style.css
+++ b/tpl/default_en/css/style.css
@@ -116,6 +116,7 @@ input[type=submit] {
     display: inline-block;
     margin-left: 1em;
     margin-right: 1em;
+    margin-bottom: 0.5em;
 }
 
 #notice {
diff --git a/tpl/default_fr/css/style.css b/tpl/default_fr/css/style.css
index a6d6d2d..5cfcb69 100644
--- a/tpl/default_fr/css/style.css
+++ b/tpl/default_fr/css/style.css
@@ -116,6 +116,7 @@ input[type=submit] {
     display: inline-block;
     margin-left: 1em;
     margin-right: 1em;
+    margin-bottom: 0.5em;
 }
 
 #notice {