Redmine

I installed release notes in redmine v2.2.2

I can add it in Modules.but i can not click the tab. redmine log print out 500 error

help me。。。 i have no idea，thank you

NoMethodError (undefined method `id' for nil:NilClass):
  plugins/redmine_release_notes/app/controllers/release_notes_controller.rb:39:in `index'
  actionpack (3.2.11) lib/action_controller/metal/implicit_render.rb:4:in `send_action'
  actionpack (3.2.11) lib/abstract_controller/base.rb:167:in `process_action'
  actionpack (3.2.11) lib/action_controller/metal/rendering.rb:10:in `process_action'
  actionpack (3.2.11) lib/abstract_controller/callbacks.rb:18:in `block in process_action'
  activesupport (3.2.11) lib/active_support/callbacks.rb:458:in `_run__1587693312898574275__process_action__4335642574684714977__callbacks'
  activesupport (3.2.11) lib/active_support/callbacks.rb:405:in `__run_callback'
  activesupport (3.2.11) lib/active_support/callbacks.rb:385:in `_run_process_action_callbacks'
  activesupport (3.2.11) lib/active_support/callbacks.rb:81:in `run_callbacks'
  actionpack (3.2.11) lib/abstract_controller/callbacks.rb:17:in `process_action'
  actionpack (3.2.11) lib/action_controller/metal/rescue.rb:29:in `process_action'
  actionpack (3.2.11) lib/action_controller/metal/instrumentation.rb:30:in `block in process_action'
  activesupport (3.2.11) lib/active_support/notifications.rb:123:in `block in instrument'
  activesupport (3.2.11) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
  activesupport (3.2.11) lib/active_support/notifications.rb:123:in `instrument'
  actionpack (3.2.11) lib/action_controller/metal/instrumentation.rb:29:in `process_action'
  actionpack (3.2.11) lib/action_controller/metal/params_wrapper.rb:207:in `process_action'
  activerecord (3.2.11) lib/active_record/railties/controller_runtime.rb:18:in `process_action'
  actionpack (3.2.11) lib/abstract_controller/base.rb:121:in `process'
  actionpack (3.2.11) lib/abstract_controller/rendering.rb:45:in `process'
  actionpack (3.2.11) lib/action_controller/metal.rb:203:in `dispatch'
  actionpack (3.2.11) lib/action_controller/metal/rack_delegation.rb:14:in `dispatch'
  actionpack (3.2.11) lib/action_controller/metal.rb:246:in `block in action'
  actionpack (3.2.11) lib/action_dispatch/routing/route_set.rb:73:in `call'
  actionpack (3.2.11) lib/action_dispatch/routing/route_set.rb:73:in `dispatch'
  actionpack (3.2.11) lib/action_dispatch/routing/route_set.rb:36:in `call'
  journey (1.0.4) lib/journey/router.rb:68:in `block in call'
  journey (1.0.4) lib/journey/router.rb:56:in `each'
  journey (1.0.4) lib/journey/router.rb:56:in `call'
  actionpack (3.2.11) lib/action_dispatch/routing/route_set.rb:601:in `call'
  rack-openid (1.3.1) lib/rack/openid.rb:98:in `call'
  actionpack (3.2.11) lib/action_dispatch/middleware/best_standards_support.rb:17:in `call'
  rack (1.4.1) lib/rack/etag.rb:23:in `call'
  rack (1.4.1) lib/rack/conditionalget.rb:25:in `call'
  actionpack (3.2.11) lib/action_dispatch/middleware/head.rb:14:in `call'
  actionpack (3.2.11) lib/action_dispatch/middleware/params_parser.rb:21:in `call'
  actionpack (3.2.11) lib/action_dispatch/middleware/flash.rb:242:in `call'
  rack (1.4.1) lib/rack/session/abstract/id.rb:205:in `context'
  rack (1.4.1) lib/rack/session/abstract/id.rb:200:in `call'
  actionpack (3.2.11) lib/action_dispatch/middleware/cookies.rb:341:in `call'
  activerecord (3.2.11) lib/active_record/query_cache.rb:64:in `call'
  activerecord (3.2.11) lib/active_record/connection_adapters/abstract/connection_pool.rb:479:in `call'
  actionpack (3.2.11) lib/action_dispatch/middleware/callbacks.rb:28:in `block in call'
  activesupport (3.2.11) lib/active_support/callbacks.rb:405:in `_run__2832407224400065029__call__3325072935678246869__callbacks'
  activesupport (3.2.11) lib/active_support/callbacks.rb:405:in `__run_callback'
  activesupport (3.2.11) lib/active_support/callbacks.rb:385:in `_run_call_callbacks'
  activesupport (3.2.11) lib/active_support/callbacks.rb:81:in `run_callbacks'
  actionpack (3.2.11) lib/action_dispatch/middleware/callbacks.rb:27:in `call'
  actionpack (3.2.11) lib/action_dispatch/middleware/remote_ip.rb:31:in `call'
  actionpack (3.2.11) lib/action_dispatch/middleware/debug_exceptions.rb:16:in `call'
  actionpack (3.2.11) lib/action_dispatch/middleware/show_exceptions.rb:56:in `call'
  railties (3.2.11) lib/rails/rack/logger.rb:32:in `call_app'
  railties (3.2.11) lib/rails/rack/logger.rb:16:in `block in call'
  activesupport (3.2.11) lib/active_support/tagged_logging.rb:22:in `tagged'
  railties (3.2.11) lib/rails/rack/logger.rb:16:in `call'
  actionpack (3.2.11) lib/action_dispatch/middleware/request_id.rb:22:in `call'
  rack (1.4.1) lib/rack/methodoverride.rb:21:in `call'
  rack (1.4.1) lib/rack/runtime.rb:17:in `call'
  activesupport (3.2.11) lib/active_support/cache/strategy/local_cache.rb:72:in `call'
  rack (1.4.1) lib/rack/lock.rb:15:in `call'
  actionpack (3.2.11) lib/action_dispatch/middleware/static.rb:62:in `call'
  rack-cache (1.2) lib/rack/cache/context.rb:136:in `forward'
  rack-cache (1.2) lib/rack/cache/context.rb:245:in `fetch'
  rack-cache (1.2) lib/rack/cache/context.rb:185:in `lookup'
  rack-cache (1.2) lib/rack/cache/context.rb:66:in `call!'
  rack-cache (1.2) lib/rack/cache/context.rb:51:in `call'
  railties (3.2.11) lib/rails/engine.rb:479:in `call'
  railties (3.2.11) lib/rails/application.rb:223:in `call'
  railties (3.2.11) lib/rails/railtie/configurable.rb:30:in `method_missing'
  passenger (3.9.1.beta) lib/phusion_passenger/rack/thread_handler_extension.rb:67:in `process_request'
  passenger (3.9.1.beta) lib/phusion_passenger/request_handler/thread_handler.rb:126:in `accept_and_process_next_request'
  passenger (3.9.1.beta) lib/phusion_passenger/request_handler/thread_handler.rb:100:in `block in main_loop'
  passenger (3.9.1.beta) lib/phusion_passenger/utils/robust_interruption.rb:82:in `disable_interruptions'
  passenger (3.9.1.beta) lib/phusion_passenger/request_handler/thread_handler.rb:98:in `main_loop'
  passenger (3.9.1.beta) lib/phusion_passenger/request_handler.rb:432:in `block (3 levels) in start_threads'