Hi Steven,
You are right for the issue with the disconnected vCenter Server, i.e. it hangs until it connects to the server or network error occurs. The time it waits depends on the type of the error, if it is a socket time out error, then there is some time it tries to connect and I guess it takes a while.
As for the picking the vCenter Server back up, I'm not sure this function is automatic, i.e. you have explicitly refresh(using F5). Did you tried that?
Please note that this behaviour is observed only through the Orchestrator Client, if you go to the Web Operator Web interface (following the link on the Appliance welcome page) and try to browse the inventory by executing a workflow, it won't freeze your browser.
Thanks,
Milko