Control stepping motor via USB interface

[aforadi]

I am using a PIC 18f4500 here.
I have used this link to make the circuit. Also I am using the ULN2003 chip instead of 2803.
When I run the Delphi based software and click on Connect it says firmware version unknown and device not connected.
I have spent a lot of time understanding at the code but can't seem to understand where I am going wrong. Reading the main.pas file in the delphi6 folder,
I have realized that in the following code the first condition is always true. Why could this be happening any possible reason?
if (_MPUSBGetDeviceCount(vid_pid)=0) then
begin
StatusBar1.Panels[1].text:='Status : DeviceGCH not connected';
StatusBar1.Panels[0].text:='Firmware version : unkhown';
exit;
end
else
begin
StatusBar1.Panels[1].text:='Status : Device connected';
end;

 

[aforadi]

Oops..The link is Control stepping motor via USB interface PIF18F4550