You just need to start alcohol120, then open the mds or mdf (can't remember which but the correct extension is shown in the filetype selection) then burn the cd. Use x1 speed like you said.
To upgrade just switch the ignition on, put the disk in and follow the instructions.
If it fails and you can't eject the disk, just leave the car switched off for about 25 mins, then unlock and hit the eject button quickly.