MIt is already in the program. This is how the end of the program posts:
;Version _2.6 of the firmware can abort the print too early if the file ends
;too soon. However if the file hasn't ended yet because there are comments at
;the end of the file, it won't abort yet. Therefore we have to put at least 512
;bytes at the end of the g-code so that the file is not yet finished by the
;time that the motion planner gets flushed. With firmware version _3.3 this
;should be fixed, so this comment wouldn't be necessary any more. Now we have
;to pad this text to make precisely 512 bytes.
;Comment to stop blob and grinding
;Comment to stop blob and grinding
;Comment to stop blob and grinding
;Comment to stop blob and grinding
M25; Stop reading from this point
I have tried every combination. With and without the M25, also with and without the Comment.
Tony