In Samplitude Music Studio, when I open the MIDI Editor and try to play the notes by clicking on the piano roll. I cannot hear any sound. Any ideas on which option I should select in order to hear the sounds?
Provided you have configured a functional audio driver in Music Studio and your sound output from the program is generally working, this is probably just a matter of settings in the MIDI Editor dialog.
First of all, when you're in the MIDI Editor and looking at your piano roll, open the "Options" menu (of the MIDI Editor) and make sure the "Play clicked notes" option is ticked. Then, make sure in the instrument/output selection, which is a drop-down list pretty much in the upper right-hand corner of the MIDI Editor screen, that a suitable output/instrument is picked here. You don't want to accidentally send the MIDI data to some external MIDI device that isn't even hooked up. Just pick one of the provided software instruments from the Revolta or Vita synth or your own VSTi plug-ins. Now click on the piano roll again. Should work.