plugin download mfp m127fw under ubuntu 15.10 fails

first tried to install mfpm127fw under genuine hplip of ubuntu 15.10 (hplip homepage says it should work)
had the same problem as
https://bugs.launchpad.net/hplip/+bug/1476920
then manually installed the actual hplip sw (3.15.11)
now the download of the required plugin fails (with hp-setup, hp-plugin and all combinations with su/sudo)

is there any chance to get the plugin by mail?/other download site
which ports of the firewall need to be open?

the printer doesn't work with JetDirect either

please answer as soon as possible - otherwise I have to return the printer within 1 week

attached the terminal responses:
(after several minutes I stopped the process with Ctrl + c)
hp-plugin

HP Linux Imaging and Printing System (ver. 3.15.11)
Plugin Download and Install Utility ver. 2.1

Copyright (c) 2001-15 HP Development Company, LP
This software comes with ABSOLUTELY NO WARRANTY.
This is free software, and you are welcome to distribute it
under certain conditions. See COPYING file for more details.

HP Linux Imaging and Printing System (ver. 3.15.11)
Plugin Download and Install Utility ver. 2.1

Copyright (c) 2001-15 HP Development Company, LP
This software comes with ABSOLUTELY NO WARRANTY.
This is free software, and you are welcome to distribute it
under certain conditions. See COPYING file for more details.

Checking for network connection...
Downloading plug-in from:
Receiving digital keys: /usr/bin/gpg --homedir /home/stephan/.hplip/.gnupg --no-permission-warning --keyserver pgp.mit.edu --recv-keys 0x4ABA2F66DBD5A95894910E0673D770CDA59047B9
Creating directory plugin_tmp
Verifying archive integrity... All good.
Uncompressing HPLIP 3.15.11 Plugin Self Extracting Archive................................................

HP Linux Imaging and Printing System (ver. 3.15.11)
Plugin Installer ver. 3.0

Copyright (c) 2001-15 HP Development Company, LP
This software comes with ABSOLUTELY NO WARRANTY.
This is free software, and you are welcome to distribute it
under certain conditions. See COPYING file for more details.

Plug-in version: 3.15.11
Installed HPLIP version: 3.15.11
Number of files to install: 42

|^CTraceback (most recent call last):
  File "./plugin_install.py", line 249, in <module>
    ok = installPlugin()
  File "./plugin_install.py", line 56, in installPlugin
    status, output = utils.run(cmd, passwordObj)
  File "/usr/share/hplip/base/utils.py", line 1275, in run
    i = child.expect(EXPECT_LIST)
  File "/usr/share/hplip/base/pexpect/__init__.py", line 1418, in expect
    timeout, searchwindowsize)
  File "/usr/share/hplip/base/pexpect/__init__.py", line 1433, in expect_list
    timeout, searchwindowsize)
  File "/usr/share/hplip/base/pexpect/__init__.py", line 1502, in expect_loop
    c = self.read_nonblocking(self.maxread, timeout)
  File "/usr/share/hplip/base/pexpect/__init__.py", line 901, in read_nonblocking
    r, w, e = self.__select([self.child_fd], [], [], timeout)
  File "/usr/share/hplip/base/pexpect/__init__.py", line 1687, in __select
    return select.select(iwtd, owtd, ewtd, timeout)
KeyboardInterrupt
error: Python gobject/dbus may be not installed
error: Plug-in install failed.

Done.