The windrvr6.dll is loaded at startup by wdreg.exe.
The wdapi1000.dll has driver helper functions..
The usb_diag application can be used to diagnose driver problems.
DppUsbCe.dll provides usb interface functions for CE USB communications.
Applications and the CE DppApi communicate with the DppUsbCe.dll (See the USB sample code).
The CE DppApi is provided for rapid application development (See the Test_CE_DPP sample code).