Installation & Start up Cubase LE 5

Hi:
I’m very new to any Cubase Software so can someone quickly help me with this problem:
I have successfully installed the Cubase LE 5 and have also (hopefully) correctly set up my audio-devices which are:

  • ASIO-low latency Output Driver from MIDITECH’s Guitarface II USB Audio Interface
  • MIDI Output Driver: CoolSoft VirtualMIDISynth
  • I have Pentium IV Dual Core PC and running VISTA Windows (Home Premium).

After spending a lot of time I can NOT figure out why I’m NOT getting any sound out of the Cubase LE 5 while I’m trying to playback a simple MIDI-file. NOTE: using the exactly the same Drivers configuration and playing back the same MIDI-file using another, ‘Band-in-a-Box’ (from PG Music) sequencer - I’m getting full sound without any problems…!

Is there any other critical setting/s in Cubase LE 5 which I have to make or check out to resolve this ‘no sound’ problem?
Any suggestions/advice would be greatly appreciated.