Tapi unit

Hello experts,
I'm undergraduated student and I study computer system. My project is an Answer machine using
a voice modem, and offcourse I use Delphi (5 Enterprise). I found a unit called TAPI at www.delphi-jedi.org at API section, which can be used with voice modem to access it's special properties such as playing voice, and detecting telephone buttons. My problem is that I cann't find a starting
point to use this unit (it seem that this unit has been translated from C++ language to Delphi). My quesion is:

1. How can initialize  telphone line to use modem.
2. How can I use this unit to dial a number.
3. How can I use this unit to detect ring.
4. How can I play a wav file into telephone line.

Note;
 unit i use is:
  Tapi_d.zip
  Tapi_j.zip
  tapi1_j.zip
u find it in that address

Thanks in advance
Abdelghani