What is it about the Device Descriptor that makes it a composite device?
I created one of your composite devices on a Freescale based embedded system and looked at the device descriptor on the host (Windows) side and there are a number of "Unknown Descriptors" looking like
05 24 00 10 01
(this is from MS usbview.exe utility)
What are these? The descriptor type 0x24 is from the USB 3 spec and is called "USB_DT_PIPE_USAGE" - I searched for this in the 188.8.131.52 sources and couldn't find any references. This leads me to think some trash has been included in the device decriptors. But then again I could have missed something.