Henrik, the link only works for me if I right-click and select open in new window ?, very strange.

mister_e, ok thanks for that, I would never have found this package if you hadn't told me about it, the microchip website has nothing that indicates to me where to find the bootloader, anyways, I have downloaded the package and found the bootloader for my device already as a hex and I've made some progress.
I have programmed the bootloader into my device and it is recognised by the PC bootloader program and I can use it to put my main program into the device.

Next problem, I dont know how to switch between bootloader mode and running my main program ?.

I have this line in my main program:-

Define RESET_ORG 0x800 'To use this device with the Microchip USB Bootloader

I noticed that it puts the bootloader portion at the beginning of memory rather than end (which I expected)

Any ideas