[Nitro] Blog explodes -> newby needs help

[Aureliano Calvo]

With Jo's help at IRC I've been able to set up nitro and start the
blog using sqlite3 as the data store. But when I go to the admin link
to create a new post I get an exception in the log and a "white screen
of death" in my browser.

What I did:
Go to http://localhost:9000/admin/og/create/Post and created a new post.

Exception in the log (with some context):
DEBUG: INSERT INTO ogpost (oid, author, title, access_time,
category_oid, update_time, body, create_time) VALUES
('copIeGllar3j0Iaa-JKF1G', 'aure', 'Blog test', NULL,
'bkpeKaljqr3lLJaa-JKF1G', '2007-07-07 14:36:12', 'This is a blog
test', '2007-07-07 14:36:12')
ERROR: Error while handling '/admin/og/save'
ERROR: undefined method `unsaved?' for nil:NilClass
  (eval):25:in `add_tag'
  /home/aure/nitro/script/lib/../../og/lib/og/collection.rb:258:in `send'
  /home/aure/nitro/script/lib/../../og/lib/og/collection.rb:258:in
`save_building_members'
  /home/aure/nitro/script/lib/../../og/lib/og/collection.rb:257:in `each'
  /home/aure/nitro/script/lib/../../og/lib/og/collection.rb:257:in
`save_building_members'
  /home/aure/nitro/script/lib/../../og/lib/og/model.rb:179:in
`save_building_collections'
  /home/aure/nitro/script/lib/../../og/lib/og/model.rb:176:in `each'
  /home/aure/nitro/script/lib/../../og/lib/og/model.rb:176:in
`save_building_collections'
  /home/aure/nitro/script/lib/../../og/lib/og/store.rb:98:in `save'
  /home/aure/nitro/script/lib/../../og/lib/og/model.rb:20:in `save'
  /home/aure/nitro/script/lib/../../og/lib/og/manager.rb:118:in `with_store'
  /home/aure/nitro/script/lib/../../og/lib/og/model.rb:19:in `save'
  /home/aure/nitro/script/lib/../../nitro/lib/nitro/part/admin/og/controller.rb:101:in
`save'
  (eval):4:in `call'
  (eval):4:in `save'
  (eval):4:in `call'
  (eval):4:in `save'
  (eval):3:in `call'
  (eval):3:in `save'
  /home/aure/nitro/script/lib/../../raw/lib/raw/compiler.rb:65:in `send'
  /home/aure/nitro/script/lib/../../raw/lib/raw/compiler.rb:65:in `save___super'
  /home/aure/nitro/script/lib/../../raw/lib/raw/controller/publishable.rb:36:in
`send'
  /home/aure/nitro/script/lib/../../raw/lib/raw/controller/publishable.rb:36:in
`method_missing'
  /home/aure/nitro/script/lib/../../raw/lib/raw/adapter.rb:69:in `send'
  /home/aure/nitro/script/lib/../../raw/lib/raw/adapter.rb:69:in
`handle_context'
  /home/aure/nitro/script/lib/../../raw/lib/raw/adapter/webrick.rb:134:in
`do_POST'
  /usr/lib/ruby/1.8/webrick/httpservlet/abstract.rb:35:in `__send__'
  /usr/lib/ruby/1.8/webrick/httpservlet/abstract.rb:35:in `service'
  /usr/lib/ruby/1.8/webrick/httpserver.rb:104:in `service'
  /usr/lib/ruby/1.8/webrick/httpserver.rb:65:in `run'
  /usr/lib/ruby/1.8/webrick/server.rb:173:in `start_thread'
  /usr/lib/ruby/1.8/webrick/server.rb:162:in `start'
  /usr/lib/ruby/1.8/webrick/server.rb:162:in `start_thread'
  /usr/lib/ruby/1.8/webrick/server.rb:95:in `start'
  /usr/lib/ruby/1.8/webrick/server.rb:92:in `each'
  /usr/lib/ruby/1.8/webrick/server.rb:92:in `start'
  /usr/lib/ruby/1.8/webrick/server.rb:23:in `start'
  /usr/lib/ruby/1.8/webrick/server.rb:82:in `start'
  /home/aure/nitro/script/lib/../../raw/lib/raw/adapter/webrick.rb:57:in `start'
  /home/aure/nitro/script/lib/../../nitro/lib/nitro/application.rb:123:in
`start'
  app.rb:22
  LOGGED FROM: /home/aure/nitro/script/lib/../../raw/lib/raw/adapter.rb:83:in
`handle_context'