Install - Unistall Process

Hello!
I just got Unity Editor on my Ubuntu 14.04LTS machine. When I first tried to install it , through dpkg I get dependencies error. Then I though that if I use Software Center may the installation succeed. Well, when I opened the package in Software Center I got the screen of REINSTALLING the package. Well this was unexpected. The system though that the package was installed, which was not - more like broken I would say.
Anyway I hit the reinstall button, wait some time and everything installed and work properly!!!

Now to check for bugs in unistallation process, I try to find and unistall the editor. First I run the following command :

sudo apt-get remove unity-editor

And I get the following error:

E: The package unity-editor needs to be reinstalled, but I can't find an archive for it.

Ok that's not cool. I try to run a check-for-broken-dependencies command using :

sudo apt-get check

and again, the above error message came up to my screen. Next I though that might can find the package in Ubuntu Software Center, from where I installed it. When I opened it, the software center crashed! I run it from my terminal so I can trace the errors. Here is the log, with some important notes I discovered in bold:

2015-08-29 15:29:15,795 - softwarecenter.ui.gtk3.app - INFO - setting up proxy 'None'
2015-08-29 15:29:16,420 - softwarecenter.backend.reviews - WARNING - Could not get usefulness from server, no username in config file
2015-08-29 15:29:16,422 - softwarecenter.plugin - INFO - activating plugin '<module 'webapps_activation' from '/usr/share/software-center/softwarecenter/plugins/webapps_activation.pyc'>'
2015-08-29 15:29:16,510 - softwarecenter.db.pkginfo_impl.aptcache - INFO - aptcache.open()
2015-08-29 15:29:17,443 - softwarecenter.backend.reviews - WARNING - error creating bsddb: '(22, 'Invalid argument -- BDB0054 illegal flag combination specified to DB_ENV->open')' (corrupted?)
2015-08-29 15:29:17,443 - softwarecenter.backend.reviews - ERROR - trying to repair DB failed
Traceback (most recent call last):
File "/usr/share/software-center/softwarecenter/backend/reviews/__init__.py", line 358, in _save_review_stats_cache_blocking
self._dump_bsddbm_for_unity(outfile, outdir)
File "/usr/share/software-center/softwarecenter/backend/reviews/__init__.py", line 377, in _dump_bsddbm_for_unity
0600)
DBInvalidArgError: (22, 'Invalid argument -- BDB0054 illegal flag combination specified to DB_ENV->open')
/usr/lib/python2.7/dist-packages/gi/overrides/GLib.py:535: Warning: Source ID 68 was not found when attempting to remove it
return super(MainContext, self).iteration(may_block)
Traceback (most recent call last):
File "/usr/share/software-center/softwarecenter/db/pkginfo_impl/aptcache.py", line 261, in open
self._cache = apt.Cache(progress)
File "/usr/lib/python2.7/dist-packages/apt/cache.py", line 107, in __init__
self.open(progress)
File "/usr/lib/python2.7/dist-packages/apt/cache.py", line 152, in open
self._depcache = apt_pkg.DepCache(self._cache)
SystemError: E:The package unity-editor needs to be reinstalled, but I can't find an archive for it.
2015-08-29 15:29:18,215 - softwarecenter.db.enquire - ERROR - _get_estimate_nr_apps_and_nr_pkgs failed
Traceback (most recent call last):
File "/usr/share/software-center/softwarecenter/db/enquire.py", line 115, in _get_estimate_nr_apps_and_nr_pkgs
tmp_matches = enquire.get_mset(0, len(self.db), None, xfilter)
File "/usr/share/software-center/softwarecenter/db/appfilter.py", line 89, in __call__
if (not pkgname in self.cache and
File "/usr/share/software-center/softwarecenter/db/pkginfo_impl/aptcache.py", line 281, in __contains__
return self._cache.__contains__(k)
AttributeError: 'NoneType' object has no attribute '__contains__'
Traceback (most recent call last):
File "/usr/bin/software-center", line 183, in <module>
app.run(args)
File "/usr/share/software-center/softwarecenter/ui/gtk3/app.py", line 1378, in run
self.show_available_packages(args)
File "/usr/share/software-center/softwarecenter/ui/gtk3/app.py", line 1316, in show_available_packages
self.view_manager.set_active_view(ViewPages.AVAILABLE)
File "/usr/share/software-center/softwarecenter/ui/gtk3/session/viewmanager.py", line 150, in set_active_view
view_widget.init_view()
File "/usr/share/software-center/softwarecenter/ui/gtk3/panes/availablepane.py", line 227, in init_view
self.cache, self.db, self.icons, self.apps_filter)
File "/usr/share/software-center/softwarecenter/ui/gtk3/views/lobbyview.py", line 80, in __init__
self.build()
File "/usr/share/software-center/softwarecenter/ui/gtk3/views/lobbyview.py", line 326, in build
self._build_homepage_view()
File "/usr/share/software-center/softwarecenter/ui/gtk3/views/lobbyview.py", line 121, in _build_homepage_view
self._append_whats_new()
File "/usr/share/software-center/softwarecenter/ui/gtk3/views/lobbyview.py", line 255, in _append_whats_new
whats_new_cat = self._update_whats_new_content()
File "/usr/share/software-center/softwarecenter/ui/gtk3/views/lobbyview.py", line 240, in _update_whats_new_content
docs = whats_new_cat.get_documents(self.db)
File "/usr/share/software-center/softwarecenter/db/categories.py", line 131, in get_documents
nonblocking_load=False)
File "/usr/share/software-center/softwarecenter/db/enquire.py", line 330, in set_query
self._blocking_perform_search()
File "/usr/share/software-center/softwarecenter/db/enquire.py", line 225, in _blocking_perform_search
matches = enquire.get_mset(0, self.limit, None, xfilter)
File "/usr/share/software-center/softwarecenter/db/appfilter.py", line 89, in __call__
if (not pkgname in self.cache and
File "/usr/share/software-center/softwarecenter/db/pkginfo_impl/aptcache.py", line 281, in __contains__
return self._cache.__contains__(k)
AttributeError: 'NoneType' object has no attribute '__contains__'
​

So the main question is what is going wrong with my Unistall process? Why the installation broke after reinstalling the software several times? And why Software Center now crash as well as my Update Manager?
How to fix the errors and unistall the editor?