The MCS is capable of handling multiple devices and/or replays simultanously. For connecting more than one device use either the Connect, Network Connection, Create Pseudo Spectran or Load Measurement File menu entries.
At the moment each graphic view can only handle data from a single device. You can select the data source for each view by first activating the view and then selecting the device via the dropdown box in the bottom-right corner. This will display the serial number and model for USB devices, the IP address or hostname for network connections and the recording date for replays.
When the datasource is changed each view will adjust itself to the new parameters. Usually this will involve a complete reset of the views data and adjustments to Reference Level and Dynamic Range.
If a device is disconnected all views associated to it will be assigned to another datasource if possible.