If you actually have the bootstrap-sass code checked out, change this line in the .gemspec:
s.add_runtime_dependency 'sass', '~> 3.3.0'
to
s.add_runtime_dependency 'sass', '~> 3.2.0'
After this, run bundle update sass
, then bundle clean --force
. The problem when downgrading the sass gem is that compass still tries to load the newer one, that's why you need the clean (or you could do a gem uninstall
if it suits you better).