You need a BMW ICOM emulator (icom a2, icom a3 or icom next clone…all ok); maybe a cheap K+DCAN usb cable is enough to do this. It depends on your budget.
And working software guarantees your success! Spend some dollars to get tested bmw software, even crack versions ok; it’ll better than download on webs for free, usually with unknown security and functionality. This is a site you can trust in:
Here are the Winkfp guide with detailed steps…
The important note– if you flash the DME with WinKFP it will change the VIN to the one you type. If not, Tool32 can do it. (With tool 32 you must enter 18 )
However depending on DME, you may not be able to use a second hand DME to another car because of ISN issues.
You may also need to code it after flashing.