Not sure thats the best way to go about it. The USB enumeration process is very complex and mainly boilerplate (ie. unrelated to your situation). The volume of traffic can be quite overwhelming, even with a pukka USB analyser. Its probably easier to understand by looking at the code on the PC and on the PIC in tandem. One simple rule is that the device (PIC) will never send data unless requested by the host (PC). There are many software only tools that will display HID host/device transactions (just the data not the overhead).

George