With 0.9.4 I've made an important change: all nodes and message are no longer traced by default. Tracing only works on a selection of nodes.
Also msg tracing and sending messages to debug are two separate operations, neither by default working all nodes and flows.
Instead a selection of nodes must be made - upon which to act - or if you really want to trace and debug everything there is an extra "All nodes?" checkbox that can be used to confirm that desire.
I think this will prevent accidental damage and frustration.
