diff --git a/.travis.yml b/.travis.yml
index 01f9a56..dca51b1 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,68 +2,53 @@ language: php
 
 sudo: false
 
+addons:
+  firefox: "47.0.1"
+  postgresql: "9.3"
+  apt:
+    packages:
+      - oracle-java8-installer
+      - oracle-java8-set-default
+
 cache:
   directories:
     - $HOME/.composer/cache
+    - $HOME/.npm
 
 php:
  - 5.6
  - 7.0
+ - 7.1
 
 env:
-  - MOODLE_BRANCH=MOODLE_31_STABLE DB=mysqli
-  - MOODLE_BRANCH=MOODLE_30_STABLE DB=pgsql
-  - MOODLE_BRANCH=MOODLE_29_STABLE DB=mysqli
-  - MOODLE_BRANCH=MOODLE_28_STABLE DB=pgsql
-  - MOODLE_BRANCH=MOODLE_27_STABLE DB=mysqli
-
-matrix:
-  exclude:
-    - php: 7.0
-      env: MOODLE_BRANCH=MOODLE_29_STABLE DB=mysqli
-    - php: 7.0
-      env: MOODLE_BRANCH=MOODLE_28_STABLE DB=pgsql
-    - php: 7.0
-      env: MOODLE_BRANCH=MOODLE_27_STABLE DB=mysqli
-    - php: 5.6
-      env: MOODLE_BRANCH=MOODLE_31_STABLE DB=mysqli
-    - php: 5.6
-      env: MOODLE_BRANCH=MOODLE_30_STABLE DB=pgsql
-    - php: 5.6
-      env: MOODLE_BRANCH=MOODLE_29_STABLE DB=mysqli
-    - php: 5.6
-      env: MOODLE_BRANCH=MOODLE_28_STABLE DB=pgsql
-    - php: 5.6
-      env: MOODLE_BRANCH=MOODLE_27_STABLE DB=mysqli
-  include:
-    - php: 5.4
-      env: MOODLE_BRANCH=MOODLE_31_STABLE DB=mysqli
-    - php: 5.4
-      env: MOODLE_BRANCH=MOODLE_30_STABLE DB=pgsql
-    - php: 5.4
-      env: MOODLE_BRANCH=MOODLE_29_STABLE DB=mysqli
-    - php: 5.4
-      env: MOODLE_BRANCH=MOODLE_28_STABLE DB=pgsql
-    - php: 5.4
-      env: MOODLE_BRANCH=MOODLE_27_STABLE DB=mysqli
+ global:
+  - MOODLE_BRANCH=MOODLE_32_STABLE IGNORE_PATHS=quizzes,lang
+  - MOODLE_BRANCH=MOODLE_33_STABLE IGNORE_PATHS=quizzes,lang
+ matrix:
+  - DB=pgsql
+  - DB=mysqli
 
 before_install:
   - phpenv config-rm xdebug.ini
+  - nvm install 8.9
+  - nvm use 8.9
   - cd ../..
-  - composer selfupdate
-  - composer create-project -n --no-dev --prefer-dist moodlerooms/moodle-plugin-ci ci ^1
+  - composer create-project -n --no-dev --prefer-dist moodlerooms/moodle-plugin-ci ci ^2
   - export PATH="$(cd ci/bin; pwd):$(cd ci/vendor/bin; pwd):$PATH"
 
 install:
-  - moodle-plugin-ci add-plugin wiris/moodle-filter_wiris
-  - moodle-plugin-ci add-plugin wiris/moodle-qtype_wq
+  - moodle-plugin-ci add-plugin --branch development wiris/moodle-filter_wiris
+  - moodle-plugin-ci add-plugin --branch development wiris/moodle-qtype_wq
   - moodle-plugin-ci install
+
 script:
   - moodle-plugin-ci phplint
   - moodle-plugin-ci phpcpd
   - moodle-plugin-ci phpmd
   - moodle-plugin-ci codechecker
-  - moodle-plugin-ci shifter
   - moodle-plugin-ci validate
+  - moodle-plugin-ci savepoints
+  - moodle-plugin-ci mustache
+  - moodle-plugin-ci grunt -t css
   - moodle-plugin-ci phpunit
   - moodle-plugin-ci behat
diff --git a/question.php b/question.php
index 4874fb9..048b39d 100644
--- a/question.php
+++ b/question.php
@@ -100,7 +100,6 @@ private function set_shortanswer_matching_answers(array $response) {
                             $needsgrade = true;
                         }
                     }
-                    
                 }
             }
 
@@ -123,7 +122,7 @@ private function set_shortanswer_matching_answers(array $response) {
             if (empty($qimpl->assertions)) {
                 $qimpl->setAssertion("equivalent_symbolic", 0, 0);
             }
-            
+
             // Remove all non-syntactic assertions from question and save to $assertions array.
             for ($i = $qimpl->assertions->length - 1; $i >= 0; $i--) {
                 $assertion = $qimpl->assertions[$i];
diff --git a/renderer.php b/renderer.php
index 19adf73..f577c1f 100644
--- a/renderer.php
+++ b/renderer.php
@@ -61,7 +61,7 @@ public function __construct($subq) {
     }
     // Shortanswerwiris grading.
     public function get_matching_answer(array $response) {
-        if (isset($response['answer'])) {
+        if (isset($response['answer']) || $response['answer'] == null) {
             if (!empty($response['correct_response'])) {
                 // This is called to produce de feedback popup "The correct response is ...".
                 return $this->subq->base->get_matching_answer($this->subq->base->get_correct_response());
@@ -128,11 +128,11 @@ public function subquestion(question_attempt $qa, question_display_options $opti
         $size = 1;
         if (class_exists('core_text')) {
             if ($response != null) {
-                //  Plain response, the size of the input is the same that the size of the response.
-                if (substr($response, 0, 5) != "<math"){
+                // Plain response, the size of the input is the same that the size of the response.
+                if (substr($response, 0, 5) != "<math") {
                     $size = max(1, core_text::strlen(trim($response)) + 1);
                 } else {
-                    $size = $qa->get_question()->expand_variables_text($response) +1;
+                    $size = $qa->get_question()->expand_variables_text($response) + 1;
 
                 }
             } else {
@@ -142,11 +142,11 @@ public function subquestion(question_attempt $qa, question_display_options $opti
             }
         } else {
             if ($response != null) {
-                //  Plain response, the size of the input is the same that the size of the response.
-                if (substr($response, 0, 5) != "<math"){
+                // Plain response, the size of the input is the same that the size of the response.
+                if (substr($response, 0, 5) != "<math") {
                     $size = max(1, textlib::strlen(trim($response)) + 1);
                 } else {
-                    $size = $qa->get_question()->expand_variables_text($response) +1;
+                    $size = $qa->get_question()->expand_variables_text($response) + 1;
 
                 }
             } else {
diff --git a/version.php b/version.php
index 90d3cd0..74cd632 100644
--- a/version.php
+++ b/version.php
@@ -16,11 +16,11 @@
 
 defined('MOODLE_INTERNAL') || die();
 
-$plugin->version = 2017110600;
+$plugin->version = 2017112300;
 $plugin->release = '3.58.0.1029';
 $plugin->requires = 2011060313;
 $plugin->maturity = MATURITY_STABLE;
 $plugin->component = 'qtype_multianswerwiris';
 $plugin->dependencies = array (
-     'qtype_wq' => 2017110600
+     'qtype_wq' => 2017112300
 );