diff --git a/app/corpora/views.py b/app/corpora/views.py
index 1a220499..dc4d4ade 100644
--- a/app/corpora/views.py
+++ b/app/corpora/views.py
@@ -1,4 +1,4 @@
-from flask import (abort, current_app, flash, redirect, request,
+from flask import (abort, current_app, flash, make_response, redirect, request,
                    render_template, url_for, send_from_directory)
 from flask_login import current_user, login_required
 from threading import Thread
@@ -99,8 +99,8 @@ def add_corpus_file(corpus_id):
         for corpus_file in corpus.files:
             if filename == corpus_file.filename:
                 flash('File already registered to this corpus.')
-                return redirect(url_for('corpora.add_corpus_file',
-                                        corpus_id=corpus_id))
+                return make_response({'redirect_url': url_for('corpora.corpus', corpus_id=corpus.id)}, 500)
+                # return redirect(url_for('corpora.add_corpus_file', corpus_id=corpus_id))
         # Save the file
         dir = os.path.join(str(corpus.user_id), 'corpora', str(corpus.id))
         file.save(os.path.join(current_app.config['NOPAQUE_STORAGE'],
@@ -125,7 +125,10 @@ def add_corpus_file(corpus_id):
                               corpus_file.id))
         thread.start()
         flash('Corpus file added!')
-        return redirect(url_for('corpora.corpus', corpus_id=corpus_id))
+        return make_response(
+            {'redirect_url': url_for('corpora.corpus', corpus_id=corpus.id)},
+            201)
+        # return redirect(url_for('corpora.corpus', corpus_id=corpus_id))
     return render_template('corpora/add_corpus_file.html.j2',
                            add_corpus_file_form=add_corpus_file_form,
                            corpus=corpus, title='Add corpus file')
diff --git a/app/models.py b/app/models.py
index f8e6fbc6..d4044e57 100644
--- a/app/models.py
+++ b/app/models.py
@@ -426,6 +426,24 @@ class CorpusFile(db.Model):
         self.corpus.status = 'unprepared'
         db.session.commit()
 
+    def to_dict(self):
+        return {'id': self.id,
+                'address': self.address,
+                'author': self.author,
+                'booktitle': self.booktitle,
+                'chapter': self.chapter,
+                'dir': self.dir,
+                'editor': self.editor,
+                'filename': self.filename,
+                'institution': self.institution,
+                'journal': self.journal,
+                'pages': self.pages,
+                'publisher': self.publisher,
+                'publishing_year': self.publishing_year,
+                'school': self.school,
+                'title': self.title,
+                'corpus_id': self.corpus_id}
+
 
 class Corpus(db.Model):
     """
@@ -455,6 +473,7 @@ class Corpus(db.Model):
         return {'id': self.id,
                 'creation_date': self.creation_date.timestamp(),
                 'description': self.description,
+                'files': [file.to_dict() for file in self.files],
                 'status': self.status,
                 'title': self.title,
                 'user_id': self.user_id}
diff --git a/app/templates/corpora/add_corpus_file.html.j2 b/app/templates/corpora/add_corpus_file.html.j2
index f792f0fe..beb46ba3 100644
--- a/app/templates/corpora/add_corpus_file.html.j2
+++ b/app/templates/corpora/add_corpus_file.html.j2
@@ -8,7 +8,7 @@
 </div>
 
 <div class="col s12 m8">
-  <form method="POST" enctype="multipart/form-data">
+  <form class="nopaque-job-form" data-progress-modal="progress-modal">
     {{ add_corpus_file_form.hidden_tag() }}
     <div class="card">
       <div class="card-content">
@@ -103,4 +103,16 @@
     </ul>
   </form>
 </div>
+
+<div id="progress-modal" class="modal">
+  <div class="modal-content">
+    <h4><i class="material-icons prefix">file_upload</i> Uploading files for <span class="title"></span></h4>
+    <div class="progress">
+      <div class="determinate" style="width: 0%"></div>
+    </div>
+  </div>
+  <div class="modal-footer">
+    <a href="#!" class="modal-close waves-effect waves-light btn red abort-request">Cancel</a>
+  </div>
+</div>
 {% endblock %}
diff --git a/app/templates/corpora/corpus.html.j2 b/app/templates/corpora/corpus.html.j2
index 1812f64c..fcf181c5 100644
--- a/app/templates/corpora/corpus.html.j2
+++ b/app/templates/corpora/corpus.html.j2
@@ -35,9 +35,7 @@
     </div>
     <div class="card-action right-align">
       <a href="{{ url_for('corpora.analyse_corpus', corpus_id=corpus.id) }}" class="btn disabled hide waves-effect waves-light" id="analyze"><i class="material-icons left">search</i>Analyze</a>
-      {% if corpus.files[0] is defined %}
       <a href="{{ url_for('corpora.prepare_corpus', corpus_id=corpus.id) }}" class="btn disabled hide waves-effect waves-light" id="compile"><i class="material-icons left">merge_type</i>Compile</a>
-      {% endif %}
       <a data-target="delete-corpus-modal" class="btn modal-trigger red waves-effect waves-light"><i class="material-icons left">delete</i>Delete</a>
     </div>
   </div>
@@ -121,6 +119,7 @@
     constructor(corpusId, foreignCorpusFlag) {
       this.corpusId = corpusId;
       this.foreignCorpusFlag = foreignCorpusFlag;
+
       if (this.foreignCorpusFlag) {
         nopaque.foreignCorporaSubscribers.push(this);
       } else {
@@ -131,14 +130,11 @@
     _init() {
       let corpus;
 
-      if (this.foreignCorpusFlag) {
-        corpus = nopaque.foreignCorpora[this.corpusId];
-      } else {
-        corpus = nopaque.corpora[this.corpusId];
-      }
+      corpus = (this.foreignCorpusFlag ? nopaque.foreignCorpora[this.corpusId]
+                                       : nopaque.corpora[this.corpusId]);
 
       // Status
-      this.setStatus(corpus.status);
+      this.setStatus(corpus.status, corpus.files.length);
     }
 
     _update(patch) {
@@ -167,7 +163,9 @@
     }
 
     setStatus(status) {
-      let analyzeElement, compileElement, progressIndicatorElement, statusElement;
+      let analyzeElement, compileElement, numFiles, progressIndicatorElement, statusElement;
+
+      numFiles = (this.foreignCorpusFlag ? nopaque.foreignCorpora[this.corpusId] : nopaque.corpora[this.corpusId]).files.length;
 
       progressIndicatorElement = document.getElementById("progress-indicator");
       if (["queued", "running", "start analysis", "stop analysis"].includes(status)) {
@@ -188,7 +186,7 @@
       }
 
       compileElement = document.getElementById("compile");
-      if (status === 'unprepared') {
+      if (status === "unprepared" && numFiles > 0) {
         compileElement.classList.remove("disabled", "hide");
       } else {
         compileElement.classList.add("disabled", "hide");
diff --git a/app/templates/jobs/job.html.j2 b/app/templates/jobs/job.html.j2
index bd0e7086..5b45d19a 100644
--- a/app/templates/jobs/job.html.j2
+++ b/app/templates/jobs/job.html.j2
@@ -146,6 +146,7 @@
     constructor(jobId, foreignJobFlag) {
       this.jobId = jobId;
       this.foreignJobFlag = foreignJobFlag;
+
       if (this.foreignJobFlag) {
         nopaque.foreignJobsSubscribers.push(this);
       } else {
@@ -156,11 +157,8 @@
     _init() {
       let job;
 
-      if (this.foreignJobFlag) {
-        job = nopaque.foreignJobs[this.jobId];
-      } else {
-        job = nopaque.jobs[this.jobId];
-      }
+      job = (this.foreignJobFlag ? nopaque.foreignJobs[this.jobId]
+                                 : nopaque.jobs[this.jobId]);
 
       // End date
       this.setEndDate(job.end_date);