That is the single plate set up, however as I said previously, Nismo do not manufacture there own clutch kits, so it will probably be an Exedy or Valeo brand.
Did you not notice the branding stamped on the components when you were comparing new with old?
However getting back to your original issue:
Providing the correct parts have been fitted and fitted correctly, then I can only assume that there is air still in the system, however if the pedal returns fully and there is no free play and the pedal is not "spongy" then that is strange providing you have the master cyl. push rod adjusted correctly.
Alex.