The global MIDI Monitor displays all incoming MIDI events. Click on the Window menu and select the Global MIDI Monitor to open it or press keys Ctrl+M (or Cmd+M on Mac):
This window displays all incoming MIDI messages received by Gig Performer (the first column represents time in milliseconds); you can optionally turn on the SysEx indices toggle button to see the position of each byte of a SysEx message, or turn on the MIDI Out toggle button to display outgoing MIDI messages, as well.
Double-click an entry in this window to copy it to the clipboard. Hold the Shift key while double-clicking on any entry to copy all entries to the clipboard. Hold the Alt key (Option key on a Mac) to include source MIDI device names as well.
Note: also check the supplied MIDI Monitor plugin.