Submitted foreman-debug output via rsync

I am in the same situation and we opened this without success : https://groups.google.com/forum/#!topic/foreman-users/scWe0wVx7fg

There is no error in foreman-proxy.log
Here is my full production.log about this problem :

Started POST "/hosts" for <my-ip> at 2014-02-28 10:36:51 +0000
Processing by HostsController#create as */*
  Parameters: {"utf8"=>"✓", "authenticity_token"=>"CPefdYW2RfzUewMuqh9SR7dQHqh+YnHu3ILugs5tbZQ=", "host"=>{"name"=>"test", "hostgroup_id"=>"", "compute_resource_id"=>"2", "compute_profile_id"=>"3", "environment_id"=>"1", "puppet_ca_proxy_id"=>"1", "puppet_proxy_id"=>"1", "puppetclass_ids"=>[""], "managed"=>"true", "progress_report_id"=>"[FILTERED]", "type"=>"Host::Managed", "compute_attributes"=>{"machine_type"=>"n1-standard-1-d", "network"=>"default", "external_ip"=>"0", "image_id"=>"debian-7-wheezy-v20131120"}, "mac"=>"", "domain_id"=>"1", "architecture_id"=>"1", "operatingsystem_id"=>"2", "provision_method"=>"image", "build"=>"1", "medium_id"=>"2", "ptable_id"=>"7", "disk"=>"", "root_pass"=>"[FILTERED]", "is_owned_by"=>"", "enabled"=>"1", "comment"=>"", "overwrite"=>"false"}, "capabilities"=>"image"}
Adding Compute instance for test.c.natural-expanse-490.internal
Rolling back due to a problem: [Set up compute instance test.c.natural-expanse-490.internal     2     failed     [#<Host::Managed id: nil, name: "test.c.natural-expanse-490.internal", ip: nil, last_compile: nil, last_freshcheck: nil, last_report: nil, updated_at: nil, source_file_id: nil, created_at: nil, mac: nil, root_pass: nil, serial: nil, puppet_status: 0, domain_id: 1, architecture_id: 1, operatingsystem_id: 2, environment_id: 1, subnet_id: nil, ptable_id: 7, medium_id: 2, build: true, comment: "", disk: "", installed_at: nil, model_id: nil, hostgroup_id: nil, owner_id: nil, owner_type: nil, enabled: true, puppet_ca_proxy_id: 1, managed: true, use_image: nil, image_file: nil, uuid: nil, compute_resource_id: 2, puppet_proxy_id: 1, certname: "1cbc63d8-c6e3-44c7-8743-7fab1834d57c", image_id: 5, organization_id: nil, location_id: nil, type: "Host::Managed", compute_profile_id: 3>, :setCompute]]
Failed to save: 
  Rendered hosts/_progress.html.erb (0.2ms)
  Rendered puppetclasses/_selectedClasses.html.erb (0.0ms)
  Rendered puppetclasses/_classes.html.erb (3.9ms)
  Rendered puppetclasses/_class_selection.html.erb (6.5ms)
Started GET "/tasks/43b297b1-d89c-40d0-990e-e54f587872de" for <my-ip> at 2014-02-28 10:36:52 +0000
Processing by TasksController#show as */*
  Parameters: {"id"=>"43b297b1-d89c-40d0-990e-e54f587872de"}
  Rendered tasks/_list.html.erb (0.4ms)
Completed 200 OK in 2.1ms (Views: 0.8ms | ActiveRecord: 0.2ms)
Started GET "/tasks/43b297b1-d89c-40d0-990e-e54f587872de" for <my-ip> at 2014-02-28 10:36:54 +0000
Processing by TasksController#show as */*
  Parameters: {"id"=>"43b297b1-d89c-40d0-990e-e54f587872de"}
  Rendered tasks/_list.html.erb (0.4ms)
Completed 200 OK in 2.4ms (Views: 1.0ms | ActiveRecord: 0.2ms)
  Rendered compute_resources_vms/form/_gce.html.erb (2209.0ms)
  Rendered hosts/_compute.html.erb (2608.6ms)
  Rendered common/os_selection/_architecture.html.erb (3.1ms)
  Rendered common/os_selection/_operatingsystem.html.erb (4.7ms)
  Rendered hosts/_operating_system.html.erb (11.9ms)
  Rendered hosts/_unattended.html.erb (2625.9ms)
  Rendered puppetclasses/_class_parameters.html.erb (0.0ms)
  Rendered puppetclasses/_classes_parameters.html.erb (2.5ms)
  Rendered common_parameters/_inherited_parameters.html.erb (0.1ms)
  Rendered common_parameters/_puppetclass_parameter.html.erb (1.8ms)
  Rendered common_parameters/_puppetclasses_parameters.html.erb (2.7ms)
  Rendered common_parameters/_parameter.html.erb (0.9ms)
  Rendered common_parameters/_parameters.html.erb (2.3ms)
  Rendered hosts/_form.html.erb (2801.2ms)
  Rendered hosts/new.html.erb within layouts/application (2801.6ms)
  Rendered home/_user_dropdown.html.erb (1.1ms)
Read fragment views/tabs_and_title_records-1 0.1ms
  Rendered home/_topbar.html.erb (1.9ms)
  Rendered layouts/base.html.erb (3.5ms)
Completed 200 OK in 3913.1ms (Views: 2799.1ms | ActiveRecord: 12.9ms)
Started GET "/tasks/43b297b1-d89c-40d0-990e-e54f587872de" for <my-ip> at 2014-02-28 10:36:56 +0000
Processing by TasksController#show as */*
  Parameters: {"id"=>"43b297b1-d89c-40d0-990e-e54f587872de"}
  Rendered tasks/_list.html.erb (0.4ms)
Completed 200 OK in 2.7ms (Views: 1.0ms | ActiveRecord: 0.2ms)

Upgrading to 1.4.2 does not resolve the issue. I'm unsure if its down to misconfiguration by me or a problem with foreman or the gce plugin