Originally Posted by ccfj1

Download this, MEGAUPLOAD - The leading online storage and file delivery service.

Save the rom_col3 out of a OEM navboot,
then rename it to rom_col1,
then open it with a hex editor, and edit the rom_col3 value to rom_col1.
run crc24.exe and the crc will fail, but will give you a number.
then edit the last digits the the open hex file (now edited rom_col1), and change them to the ones from the crc24.exe.
then save the now modded rom_col1.

re-run the crc24.exe against rm_col1 and it should now say OK.

Then open you new navboot, the replace rom_col1 with the new (brown) rom_col1.

Job done
I don't know, I don't have the aux heating, its an i-bus device so it should just appear on screen.