Sorry, can't remember the bootloader number.
<step operation="getvar" var="max-download-size" />
<step operation="flash" partition="partition" filename="gpt.bin" MD5="XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX" />
<step operation="flash" partition="motoboot" filename="motoboot.img" MD5="XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX" />
No, I've just downgrade the rest maintaining the bootloader from Ret DE. The system recognized that it was 4.4 Ret BR, even with Ret DE bootloader, and I could insert the OTA at root folder and install it. Since the OTA was loaded with the newest bootloader, it wasn't a problem to replace the German one...