Sometimes the Pipeline winsock will allow Agent to try to connect, but then the news server will refuse the connection. The workaround is to upgrade to the latest version of Pipeline. Various words are misspelled in the American English dictionary. If you collapse all threads while the focus is in the Message List pane, Agent will position you on the thread immediately after the one you were on. When composing a message in the composition window, changing the language for the message has no effect on the spell checker used.
Agent always uses the spell checker for the default language.
We're not sure whether the bug is in Agent or NetCruiser, but you can avoid it by taking Agent offline before closing NetCruiser. The symptom is an Invalid Page Fault in the V631P.DRV module. This problem appears to affect all Agent and Free Agent versions. That page also lists any minor compatibility problems with drivers that otherwise work fine. The option to automatically expand threads when you jump into them doesn't seem to work if you are in three-pane mode and have the focus in the body pane.