I've made some packs tailored to my needs (mostly ipcams and small footprint server). Some of them have no service declared in them.
When clicking on the "Manage packs" button in sKonf I got this
Traceback (most recent call last):
 File "/usr/local/shinken/shinken/webui/bottle.py", line 682, in _handle
  return callback(**args)
 File "/usr/local/shinken/shinken/webui/bottle.py", line 1332, in wrapper
  rv = callback(*a, **ka)
 File "/usr/local/shinken/shinken/daemons/skonfdaemon.py", line 673, in lock_version
  return f(**args)
 File "/usr/local/shinken/shinken/webui/bottle.py", line 2690, in wrapper
  return template(tpl_name, **tplvars)
 File "/usr/local/shinken/shinken/webui/bottle.py", line 2664, in template
  return TEMPLATES[tpl].render(kwargs)
 File "/usr/local/shinken/shinken/webui/bottle.py", line 2636, in render
  self.execute(stdout, kwargs)
 File "/usr/local/shinken/shinken/webui/bottle.py", line 2622, in execute
  eval(self.co, env)
 File "/usr/local/shinken/shinken/webui/plugins_skonf/packs/views/packs.tpl", line 69, in <module>
  <div id="services-{{tpl.get('name', '')}}" class='services_list'>
AttributeError: 'NoneType' object has no attribute 'get'
To fix this I just added an if clause at line 68:
66    <div class='span10'>
 67    %for _t in lst:
 68     %if len(services) != 0:
 69      %(tpl, services) = _t
 70  <div id="services-{{tpl.get('name', '')}}" class='services_list'>
 71     %if len(services) == 0:
 72   <div class="alert">No services enabled for this pack</div>
And now it seems to be working ok...

Also found another one, in "shinken/webui/plugins_skonf/packs/views/packs.tpl" at line 50 and 80. I had 404s when clicking on a service inside a pack. "elements" was written "elemments". Once corrected it works ok !