Blueprint CSS compress.rb errors

I'm trying to use the Ruby compressor for custom layout and I was just using the examples bundled with Blueprint. I installed both Bundler and ChunkyPNG, this is what I've got:

D:\bp\lib>ruby compress.rb -p project1
C:/Ruby192/lib/ruby/gems/1.9.1/gems/bundler-1.0.14/lib/bundler/spec_set.rb:87:in `block in materialize': Could not find ffi-1.0.8 in any of the sources (Bundler::GemNotFound)
from C:/Ruby192/lib/ruby/gems/1.9.1/gems/bundler-1.0.14/lib/bundler/spec_set.rb:81:in `map!'
from C:/Ruby192/lib/ruby/gems/1.9.1/gems/bundler-1.0.14/lib/bundler/spec_set.rb:81:in `materialize'
from C:/Ruby192/lib/ruby/gems/1.9.1/gems/bundler-1.0.14/lib/bundler/definition.rb:90:in `specs'
开发者_StackOverflow社区from C:/Ruby192/lib/ruby/gems/1.9.1/gems/bundler-1.0.14/lib/bundler/definition.rb:135:in `specs_for'
from C:/Ruby192/lib/ruby/gems/1.9.1/gems/bundler-1.0.14/lib/bundler/runtime.rb:11:in `setup'
from C:/Ruby192/lib/ruby/gems/1.9.1/gems/bundler-1.0.14/lib/bundler.rb:115:in `setup'
from C:/Ruby192/lib/ruby/gems/1.9.1/gems/bundler-1.0.14/lib/bundler.rb:120:in `require'
from D:/bp/lib/blueprint/blueprint.rb:5:in `<top (required)>'
from <internal:lib/rubygems/custom_require>:29:in `require'
from <internal:lib/rubygems/custom_require>:29:in `require'
from compress.rb:2:in `<main>'

I can't understand a single line of what is written there, any chance to make it work, please? Thanks

ffi gem is not installed. Try again after this command bundle install.

At last Joshua Clayton (Blueprint css author) helped me with that: http://groups.google.com/group/blueprintcss/browse_thread/thread/c19b41c2f8ea06fc/7cc3f1a0f2031295?show_docid=7cc3f1a0f2031295 The solution was to use "bundle install --without test": pretty tricky...