See the change-log for a list of new features and fixes. Most notably, this release includes VCV Bridge for routing audio between Rack and a DAW using a VST/AU effect plugin. This release enables future VSTi/AU instrument plugins with MIDI and DAW clock transport to be added in a later Rack 0.6.x update.
The Plugin Manager now handles most open-source plugins and potentially all plugins with time and help from the VCV Community.
If you are upgrading from Rack 0.5, you will need to delete or backup Rack 0.5 plugins in your "Documents/Rack/plugins" directory before launching.