diff --git a/questions.py b/questions.py
index 02e8118..b93f963 100644
--- a/questions.py
+++ b/questions.py
@@ -401,7 +401,6 @@ class QuestionInformation(Question):
     '''An instance of QuestionInformation will always have the keys:
         type (str)
         text (str)
-        answer (None or an actual answer)
         points (0.0)
     '''
     #------------------------------------------------------------------------
@@ -409,8 +408,7 @@ class QuestionInformation(Question):
         # create key/values as given in q
         super().__init__(q)
         self['text'] = self.get('text', '')
-        self['answer'] = None
-        self['points'] = 0.0  # FIXME shouldnt be defined on the test???
+        self['points'] = 0.0  # always override the points
 
     #------------------------------------------------------------------------
     # can return negative values for wrong answers
diff --git a/serve.py b/serve.py
index 153d957..87cc091 100755
--- a/serve.py
+++ b/serve.py
@@ -106,22 +106,22 @@ class Root(object):
         ans = {}
         for q in t['questions']:
             if 'answered-' + q['ref'] in kwargs:
-                ans[q['ref']] = kwargs.get(q['ref'], None)
+                # HACK: checkboxes in html return None instead of an empty list
+                # we have to manualy replace by []
+                default_ans = [] if q['type'] == 'checkbox' else None
+                ans[q['ref']] = kwargs.get(q['ref'], default_ans)
 
         # store the answers in the Test, correct it, save JSON and
         # store results in the database
         t.update_answers(ans)
-        # try:
         t.correct()
-        # except:
-        #     cherrypy.log.error('Failed to correct test of student %s' % t['number'], 'APPLICATION')
-        #     t['grade'] = None
 
         if t['save_answers']:
             t.save_json(self.testconf['answers_dir'])
         self.database.save_test(t)
 
         if t['practice']:
+            # ---- Repeat the test ----
             raise cherrypy.HTTPRedirect('/test')
 
         else:
diff --git a/test.py b/test.py
index 41ad5dc..b5355ac 100644
--- a/test.py
+++ b/test.py
@@ -1,10 +1,12 @@
 
-import os
+import os, sys
 import random
 import yaml
 import json
 import sqlite3
 from datetime import datetime
+
+# my code
 import questions
 import database
 
@@ -13,10 +15,14 @@ def read_configuration(filename, debug=False, show_points=False, show_hints=Fals
     # FIXME validar se ficheiros e directorios existem???
     if not os.path.isfile(filename):
         print('Cannot find file "%s"' % filename)
-        os.sys.exit(1)
+        sys.exit(1)
 
-    with open(filename, 'r') as f:
-        test = yaml.load(f)
+    try:
+        with open(filename, 'r') as f:
+            test = yaml.load(f)
+    except:
+        print('Error reading yaml file "{0}".'.format(filename))
+        raise
 
     # defaults:
     test['ref'] = str(test.get('ref', filename))
@@ -35,7 +41,7 @@ def read_configuration(filename, debug=False, show_points=False, show_hints=Fals
 
     if 'database' not in test:
         print('  * Missing database in the test configuration.')
-        os.sys.exit(1)
+        sys.exit(1)
 
     if isinstance(test['files'], str):
         test['files'] = [test['files']]
@@ -48,21 +54,31 @@ def read_configuration(filename, debug=False, show_points=False, show_hints=Fals
         # each question is a list of alternative versions, even if the list
         # contains only one element
         if isinstance(q, str):
-            # questions: some_ref  --> questions: [{'ref':'some_ref', 'points':1.0, ...}]
-            test['questions'][i] = [pool[q]]
+            # normalize question to a dict
+            #       - some_ref
+            # becomes
+            #       - ref: some_ref
+            #         points: 1.0
+            test['questions'][i] = [pool[q]]  # list with just one question
             test['questions'][i][0]['points'] = 1.0
+            # Note: at this moment we do not know the questions types.
+            # Some questions, like information, should have default points
+            # set to 0. That must be done later when the question is
+            # instantiated.
 
         elif isinstance(q, dict):
             if isinstance(q['ref'], str):
-                q['ref'] = [q['ref']]
-
-            p = float(q.get('points', 1.0))
+                q['ref'] = [q['ref']]       # ref is always a list
+            p = float(q.get('points', 1.0)) # default points is 1.0
 
+            # create list of alternatives, normalized
             l = []
             for r in q['ref']:
                 qq = pool[r]
                 qq['points'] = p
                 l.append(qq)
+
+            # add question (i.e. list of alternatives) to the test
             test['questions'][i] = l
 
     return test
@@ -85,14 +101,8 @@ class Test(dict):
         '''given a dictionary ans={'ref':'some answer'} updates the answers
         of the test.  FIXME: check if answer is to be corrected or not
         '''
-        for i, q in enumerate(self['questions']):
-            if q['ref'] in ans:
-                if q['type'] == 'checkbox' and ans[q['ref']] == None:
-                    # HACK: checkboxes in html return none instead of an empty list
-                    # we have to manualy replace by []
-                    q['answer'] = []
-                else:
-                    q['answer'] = ans[q['ref']]
+        for q in self['questions']:
+            q['answer'] = ans[q['ref']] if q['ref'] in ans else None
 
     # -----------------------------------------------------------------------
     def correct(self):
--
libgit2 0.21.2