Vendor sent me the schematic, but its too large to upload to the forum.
The Vendors link to their google drive for the file ishttps://docs.google.com/uc?id=0Bw-L6X55 ... t=download
It seems to have code in the zip as well as the cicuit, but does not contain any dodgy copies of dev environments etc
It still doesnt explain why the F407 USB DFU bootloader is not showing up, apart from the PNP transistor attached to USB D+ and PD6.
I suppose if PD6 was low, the USB would be reset and not enumerate, perhaps I need to pull PD6 high, so that USB D+ is definitely not being pulled high
I tried the USB DFU again, and it eventually appeared as a USB device, though not for ages.
But there don't seem to be any official STM drivers for their DFU (well if there are, they don't make it easy to find them)
So I modified the libwdi installer script for the stm32duino bootloader driver , but just changing the VID and PID values
"%~dp0wdi-simple" --vid 0x0483 --pid 0xDF11 --type 1 --name "STM32 DFU" --dest "%~dp0maple-dfu"
and it seems to work, and dfu-util gets valid data back from the board.
But thats as far as I've got!