Do you have the beer-sample bucket installed? If not login to the console manager and select the Settings tab, Sample Buckets and check the beer-sample sample bucket, then Create.
If you do have the “beer-sample” bucket installed, make sure you can connect to the cluster. Note that Fiddler and other HTTP debuggers (as well as Anti-Virus, firewalls etc) will block streaming HTTP connection that is made from client while bootstrapping.
Notice that you are using the CouchbaseClient.Get(…) method? Switch to the CouchbaseClient.ExecuteGet(…) method and check and see what the Message and Status fields have set in the returned IOperationResult return object.