diff --git a/src/calibre/ebooks/oeb/polish/download.py b/src/calibre/ebooks/oeb/polish/download.py
index 74cd7fc553..3e158c893f 100644
--- a/src/calibre/ebooks/oeb/polish/download.py
+++ b/src/calibre/ebooks/oeb/polish/download.py
@@ -43,8 +43,9 @@ def get_external_resources(container):
                 for el, attr, link in iterhtmllinks(container, name):
                     ans[link].append(name)
             elif media_type in OEB_STYLES:
-                for link in container.iterlinks(name):
-                    ans[link].append(name)
+                for link in container.iterlinks(name, get_line_numbers=False):
+                    if is_external(link):
+                        ans[link].append(name)
     return dict(ans)
 
 
@@ -99,8 +100,9 @@ def download_one(tdir, timeout, progress_report, url):
                 src = urlopen(url, timeout=timeout)
                 filename = get_filename(purl, src)
                 sz = get_content_length(src)
+            progress_report(url, 0, sz)
             dest = ProgressTracker(df, url, sz, progress_report)
-            with src:
+            with closing(src):
                 shutil.copyfileobj(src, dest)
             filename = sanitize_file_name2(filename)
             mt = guess_type(filename)
@@ -110,7 +112,7 @@ def download_one(tdir, timeout, progress_report, url):
                 raise ValueError('The external resource {} is not of a known type'.format(url))
             return True, (url, sanitize_file_name2(filename), dest.name, mt)
     except Exception as err:
-        return False, url, as_unicode(err)
+        return False, (url, as_unicode(err))
 
 
 def download_external_resources(container, urls, timeout=60, progress_report=lambda url, done, total: None):
@@ -143,10 +145,11 @@ def replacer(url_map):
 def replace_resources(container, urls, replacements):
     url_maps = defaultdict(dict)
     changed = False
-    for url, name in urls.iteritems():
+    for url, names in urls.iteritems():
         replacement = replacements.get(url)
         if replacement is not None:
-            url_maps[name][url] = container.name_to_href(replacement, name)
+            for name in names:
+                url_maps[name][url] = container.name_to_href(replacement, name)
     for name, url_map in url_maps.iteritems():
         r = replacer(url_map)
         container.replace_links(name, r)
diff --git a/src/calibre/gui2/tweak_book/download.py b/src/calibre/gui2/tweak_book/download.py
new file mode 100644
index 0000000000..8950fb41a0
--- /dev/null
+++ b/src/calibre/gui2/tweak_book/download.py
@@ -0,0 +1,251 @@
+#!/usr/bin/env python2
+# vim:fileencoding=utf-8
+# License: GPLv3 Copyright: 2016, Kovid Goyal <kovid at kovidgoyal.net>
+
+from __future__ import (unicode_literals, division, absolute_import,
+                        print_function)
+from threading import Thread
+
+from PyQt5.Qt import (
+    pyqtSignal, QWidget, QListWidget, QListWidgetItem, QLabel, Qt,
+    QVBoxLayout, QScrollArea, QProgressBar, QGridLayout, QSize)
+
+from calibre.gui2 import error_dialog, info_dialog, warning_dialog
+from calibre.gui2.tweak_book import current_container
+from calibre.gui2.tweak_book.widgets import Dialog
+from calibre.gui2.progress_indicator import WaitStack
+from calibre.ebooks.oeb.polish.download import get_external_resources, download_external_resources, replace_resources
+
+
+class ChooseResources(QWidget):
+
+    def __init__(self, parent=None):
+        QWidget.__init__(self, parent)
+        self.l = l = QVBoxLayout(self)
+        self.la = la = QLabel(_('Choose the external resources to download'))
+        la.setWordWrap(True)
+        l.addWidget(la)
+        self.items = i = QListWidget(self)
+        l.addWidget(i)
+
+    def __iter__(self):
+        for i in xrange(self.items.count()):
+            yield self.items.item(i)
+
+    def select_none(self):
+        for item in self:
+            item.setCheckState(Qt.Unchecked)
+
+    def select_all(self):
+        for item in self:
+            item.setCheckState(Qt.Checked)
+
+    @property
+    def resources(self):
+        return {i.text():self.original_resources[i.text()] for i in self if i.checkState() == Qt.Checked}
+
+    @resources.setter
+    def resources(self, resources):
+        self.items.clear()
+        self.original_resources = resources
+        for url in resources:
+            i = QListWidgetItem(url, self.items)
+            i.setCheckState(Qt.Checked)
+            i.setFlags(Qt.ItemIsUserCheckable | Qt.ItemIsEnabled)
+
+
+class DownloadStatus(QScrollArea):
+
+    def __init__(self, parent=None):
+        QScrollArea.__init__(self, parent)
+        self.setWidgetResizable(True)
+        self.w = QWidget(self)
+        self.l = QGridLayout(self.w)
+        self.setWidget(self.w)
+
+    def __call__(self, resources):
+        self.url_map = {}
+        self.labels = []
+        for url in resources:
+            p = self.url_map[url] = QProgressBar(self.w)
+            p.setRange(0, 0)
+            self.l.addWidget(p, self.l.rowCount(), 0)
+            la = QLabel('\xa0' + url)
+            self.labels.append(la)
+            self.l.addWidget(la, self.l.rowCount()-1, 1)
+        self.l.addWidget(QLabel(''))
+        self.l.setRowStretch(self.l.rowCount()-1, 10)
+
+    def progress(self, url, done, total):
+        p = self.url_map.get(url)
+        if p is not None:
+            if total > 0:
+                p.setRange(0, total)
+                p.setValue(done)
+            else:
+                p.setRange(0, 0)
+
+
+class DownloadResources(Dialog):
+
+    get_done = pyqtSignal(object, object)
+    progress = pyqtSignal(object, object, object)
+    download_done = pyqtSignal(object, object)
+    replace_done = pyqtSignal(object, object)
+
+    def __init__(self, parent=None):
+        self.resources_replaced = False
+        Dialog.__init__(self, _('Download external resources'), 'download-external-resources', parent)
+        self.state = 0
+        self.get_done.connect(self._get_done)
+        self.download_done.connect(self._download_done)
+        self.replace_done.connect(self._replace_done)
+        self.progress.connect(self.download_status.progress, type=Qt.QueuedConnection)
+
+    def setup_ui(self):
+        self.choose_resources = cr = ChooseResources(self)
+        self.download_status = ds = DownloadStatus(self)
+        self.success = s = QLabel('')
+        s.setWordWrap(True)
+        self.l = l = QVBoxLayout(self)
+        self.wait = WaitStack(_('Searching for external resources...'), cr, self)
+        self.wait.addWidget(ds), self.wait.addWidget(s)
+        self.wait.start()
+        for t, f in ((_('Select &None'), cr.select_none), (_('Select &All'), cr.select_all)):
+            b = self.bb.addButton(t, self.bb.ActionRole)
+            b.clicked.connect(f), b.setAutoDefault(False)
+        self.bb.setVisible(False)
+        l.addWidget(self.wait), l.addWidget(self.bb)
+        t = Thread(name='GetResources', target=self.get_resources)
+        t.daemon = True
+        t.start()
+
+    def get_resources(self):
+        tb = None
+        try:
+            ret = get_external_resources(current_container())
+        except Exception as err:
+            import traceback
+            ret, tb = err, traceback.format_exc()
+        self.get_done.emit(ret, tb)
+
+    def _get_done(self, x, tb):
+        if not self.isVisible():
+            return self.reject()
+        if tb is not None:
+            error_dialog(self, _('Scan failed'), _(
+                'Failed to scan for external resources, click "Show Details" for more information.'),
+                         det_msg=tb, show=True)
+            self.reject()
+        else:
+            self.wait.stop()
+            self.state = 1
+            resources = x
+            if not resources:
+                info_dialog(self, _('No external resources found'), _(
+                    'No external resources were found in this book.'), show=True)
+                self.reject()
+                return
+            self.choose_resources.resources = resources
+            self.bb.setVisible(True)
+
+    def download_resources(self, resources):
+        tb = None
+        try:
+            ret = download_external_resources(current_container(), resources, progress_report=self.progress.emit)
+        except Exception as err:
+            import traceback
+            ret, tb = err, traceback.format_exc()
+        self.download_done.emit(ret, tb)
+
+    def _download_done(self, ret, tb):
+        if not self.isVisible():
+            return self.reject()
+        if tb is not None:
+            error_dialog(self, _('Download failed'), _(
+                'Failed to download external resources, click "Show Details" for more information.'),
+                         det_msg=tb, show=True)
+            self.reject()
+        else:
+            replacements, failures = ret
+            if failures:
+                tb = ['{}\n\t{}\n'.format(url, err) for url, err in failures.iteritems()]
+                if not replacements:
+                    error_dialog(self, _('Download failed'), _(
+                        'Failed to download external resources, click "Show Details" for more information.'),
+                                det_msg='\n'.join(tb), show=True)
+                    self.reject()
+                    return
+                else:
+                    warning_dialog(self, _('Some downloads failed'), _(
+                        'Failed to download some external resources, click "Show Details" for more information.'),
+                                det_msg='\n'.join(tb), show=True)
+            self.state = 2
+            self.wait.msg = _('Updating resources in book...')
+            self.wait.start()
+            self.success.setText('<p style="text-align:center">' + ngettext(
+                'Successfully processed the external resource', 'Successfully processed {} external resources', len(replacements)).format(len(replacements)))
+            resources = self.choose_resources.resources
+            t = Thread(name='ReplaceResources', target=self.replace_resources, args=(resources, replacements))
+            t.daemon = True
+            t.start()
+
+    def replace_resources(self, resources, replacements):
+        tb = None
+        try:
+            ret = replace_resources(current_container(), resources, replacements)
+        except Exception as err:
+            import traceback
+            ret, tb = err, traceback.format_exc()
+        self.replace_done.emit(ret, tb)
+
+    def _replace_done(self, ret, tb):
+        if tb is not None:
+            error_dialog(self, _('Replace failed'), _(
+                'Failed to replace external resources, click "Show Details" for more information.'),
+                         det_msg=tb, show=True)
+            Dialog.reject(self)
+        else:
+            self.wait.setCurrentIndex(3)
+            self.state = 3
+            self.bb.clear()
+            self.resources_replaced = True
+            self.bb.setStandardButtons(self.bb.Close)
+            self.bb.setVisible(True)
+
+    def accept(self):
+        if self.state == 0:
+            return self.reject()
+        if self.state == 1:
+            resources = self.choose_resources.resources
+            self.download_status(resources)
+            self.wait.setCurrentIndex(2)
+            self.bb.setVisible(False)
+            t = Thread(name='DownloadResources', target=self.download_resources, args=(resources,))
+            t.daemon = True
+            t.start()
+            return
+        if self.state == 2:
+            return
+        self.wait.stop()
+        Dialog.accept(self)
+
+    def reject(self):
+        if self.state == 2:
+            return
+        self.wait.stop()
+        return Dialog.reject(self)
+
+    def sizeHint(self):
+        return QSize(800, 500)
+
+if __name__ == '__main__':
+    from calibre.gui2 import Application
+    import sys
+    app = Application([])
+    from calibre.gui2.tweak_book import set_current_container
+    from calibre.gui2.tweak_book.boss import get_container
+    set_current_container(get_container(sys.argv[-1]))
+    d = DownloadResources()
+    d.exec_()
+    del d, app