RE: FTDI FT232 driver for MCHPUSB?
This is an issue that is probably not going to get solved any time soon (if ever).
The problem is that the FT232 is not a CDC device. Instead, it uses a Custom USB Protocol that was developed by FTDI, which is why you need to install a driver that they provide on a CD whenever you plug in anything which uses a FT232 into your PC.
So in short, the PIC (or any other MCU/PC not running an OS which the FT232 driver supports) cannot talk to the FT232.
In order to do so you would need a PIC FT232 Host driver which is basically a port of their windows driver to the PIC. I contacted FTDI for support in doing this and at most all they would do is provide documentation on how the protocol works and the rest would have been up to me. Which would have been good enough, but they insisted that I sign a 5 year non disclosure agreement (which would have pretty much prevented me from sharing that information or even the code that I came up with, with anyone else). And that would have completely defeated the purpose of what I was trying to accomplish, not to mention the amount of effort and headache it would have taken to port their driver. So I did not pursue it any further.
I was fortunate enough to be able to change my design to use another PIC24 instead of the FTDI chip on the client side.
To do this, use the CDC USB Client Stack on the PIC24 that will be your client device and you can communicate with any serial device using the Rx and Tx pins. If you need RS232 levels instead of TTL levels then all you need to do is place an RS232 transceiver such as the MAX202 on the PIC24's Rx and Tx lines.
Then on the Host PIC24 side all you need to do is use the CDC USB Host Stack.
Hope that helped!