==> /var/log/nginx/error.log <==
2015/03/05 15:55:03 [error] 30740#0: *5 recv() failed (104: Connection reset by peer) while reading response header from upstream, client: 127.0.0.1, server: localhost, request: "GET /ajenti/ HTTP/1.1", upstream: "http://127.0.0.1:8000/", host: "localhost"

server status is started but unable to access ajenti

core.py, SSLTunnel.start, i had to increase the time.sleep right before os.unlink(cfg.name) to get ssl working.

Maybe you could create the file in __init__ and delete it in __del__ otherwise you just depend on the speed of someones hardware. In case it's swapping at the time when ajenti starts that time can't be big enough ;)

Traceback (most recent call last):
  File "/usr/lib/pymodules/python2.7/ajenti/plugins/main/main.py", line 158, in handle_message
    self.ui.dispatch_event(update['uid'], update['event'], update['params'])
  File "/usr/lib/pymodules/python2.7/ajenti/ui/__init__.py", line 72, in dispatch_event
    self.root.dispatch_event(uid, event, params)
  File "/usr/lib/pymodules/python2.7/ajenti/ui/element.py", line 382, in dispatch_event
    if child.dispatch_event(uid, event, params):
  File "/usr/lib/pymodules/python2.7/ajenti/ui/element.py", line 378, in dispatch_event
    self.event(event, params)
  File "/usr/lib/pymodules/python2.7/ajenti/ui/element.py", line 402, in event
    getattr(self, 'on_%s' % self_event)(**(params or {}))
  File "/usr/lib/pymodules/python2.7/ajenti/plugins/main/main.py", line 381, in on_switch
    child.broadcast('on_page_load')
  File "/usr/lib/pymodules/python2.7/ajenti/ui/element.py", line 356, in broadcast
    getattr(self, method)(*args, **kwargs)
  File "/usr/lib/pymodules/python2.7/ajenti/plugins/network/main.py", line 45, in on_page_load
    self.refresh()
  File "/usr/lib/pymodules/python2.7/ajenti/plugins/network/main.py", line 52, in refresh
    i.tx, i.rx = sensor.value(i.name)
  File "/usr/lib/pymodules/python2.7/ajenti/api/sensors.py", line 44, in value
    self.cache[variant] = self.measure(variant)
  File "/usr/lib/pymodules/python2.7/ajenti/plugins/network/widget.py", line 22, in measure
    v = psutil.net_io_counters(pernic=True)[device]
AttributeError: 'module' object has no attribute 'net_io_counters'

Does ajanti have any remote interface like XML-RPC(Webmin has)/SOAP or REST to integrate it with custom desktop monitoring tool?

No control panel has Built-in ruby on rails support yet, so if you write code for ruby on rails support in Ajenti, you will be look back by ruby on rails community and also by server hosting companies who looking for Ruby on Rails app management  feature. While developing please write plugin for managing phusion passenger with nginx. And also keep support for older ruby 1.8.7 MRI and Ruby Enterprise Edition - REE 1.8.7