Settings - USB Server Properties
To open Properties window of USB server just double-click on the selected USB server or click Edit > USB Server... menu item.
After that you will see Properties window of the selected USB server.
This window shows information about current connection to USB server or USB client.
You can setup a server-wide auto-connection here by changing the "Auto-connect all USB devices when they become available!" checkbox.
Click OK or Apply to save your changes.