diff --git a/Dockerfile b/Dockerfile
index ef72df0f..45ecc1f7 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,37 +1,24 @@
 FROM ubuntu:18.04
 ENV DEBIAN_FRONTEND noninteractive
-
 RUN apt-get update -qqy
 RUN apt-get install -qqy --no-install-recommends apt-utils
-
 WORKDIR /root
-RUN apt-get install -qqy build-essential libsqlite3-dev sqlite3 bzip2 \
-                         libbz2-dev zlib1g-dev libssl-dev openssl libgdbm-dev \
-                         libgdbm-compat-dev liblzma-dev libreadline-dev \
-                         libncursesw5-dev libffi-dev uuid-dev
-RUN apt-get install -qqy wget
+RUN apt-get install --no-install-recommends -qqy build-essential libsqlite3-dev sqlite3 bzip2 \
+libbz2-dev zlib1g-dev libssl-dev openssl libgdbm-dev \
+libgdbm-compat-dev liblzma-dev libreadline-dev \
+libncursesw5-dev libffi-dev uuid-dev wget ffmpeg apt-transport-https texlive-latex-base \
+texlive-full texlive-fonts-extra sox git libcairo2-dev libjpeg-dev libgif-dev && rm -rf /var/lib/apt/lists/*
 RUN wget -q https://www.python.org/ftp/python/3.7.0/Python-3.7.0.tgz
 RUN tar -xf Python-3.7.0.tgz
 WORKDIR Python-3.7.0
 RUN ./configure > /dev/null && make -s && make -s install
 RUN python3 -m pip install --upgrade pip
-RUN apt-get install -qqy libcairo2-dev libjpeg-dev libgif-dev
 COPY requirements.txt requirements.txt
 RUN python3 -m pip install -r requirements.txt
 RUN rm requirements.txt
 WORKDIR /root
 RUN rm -rf Python-3.7.0*
-
-RUN apt-get install -qqy ffmpeg
-
 ENV TZ=America/Los_Angeles
 RUN ln -snf /usr/share/zoneinfo/$TZ /etc/localtime && echo $TZ > /etc/timezone
-RUN apt-get install -qqy apt-transport-https
-RUN apt-get install -qqy texlive-latex-base 
-RUN apt-get install -qqy texlive-full
-RUN apt-get install -qqy texlive-fonts-extra
-RUN apt-get install -qqy sox
-RUN apt-get install -qqy git
-
 ENV DEBIAN_FRONTEND teletype
 ENTRYPOINT ["/bin/bash"]
diff --git a/manimlib/scene/scene.py b/manimlib/scene/scene.py
index 24166418..abd5baa7 100644
--- a/manimlib/scene/scene.py
+++ b/manimlib/scene/scene.py
@@ -780,6 +780,9 @@ class Scene(Container):
         )
         with open(file_list, 'w') as fp:
             for pf_path in partial_movie_files:
+                if os.name == 'nt':
+                    pf_path = pf_path.replace('\\', '/')
+
                 fp.write("file {}\n".format(pf_path))
 
         movie_file_path = self.get_movie_file_path()
@@ -795,8 +798,13 @@ class Scene(Container):
         ]
         if not self.includes_sound:
             commands.insert(-1, '-an')
-        subprocess.call(commands)
+
+        combine_process = subprocess.Popen(commands)
+        combine_process.wait()
+        for pf_path in partial_movie_files:
+            os.remove(pf_path)
         os.remove(file_list)
+        print("File ready at {}".format(movie_file_path))
 
         if self.includes_sound:
             sound_file_path = movie_file_path.replace(
diff --git a/manimlib/utils/output_directory_getters.py b/manimlib/utils/output_directory_getters.py
index 3e364271..a3695249 100644
--- a/manimlib/utils/output_directory_getters.py
+++ b/manimlib/utils/output_directory_getters.py
@@ -15,7 +15,7 @@ def add_extension_if_not_present(file_name, extension):
 def guarantee_existance(path):
     if not os.path.exists(path):
         os.makedirs(path)
-    return path
+    return os.path.abspath(path)
 
 
 def get_scene_output_directory(scene_class):
@@ -78,4 +78,4 @@ def get_sorted_integer_files(directory,
         elif remove_non_integer_files:
             os.remove(full_path)
     indexed_files.sort(key=lambda p: p[0])
-    return list(map(lambda p: p[1], indexed_files))
+    return list(map(lambda p: os.path.join(directory, p[1]), indexed_files))