In Soundshaper I have a default set of values for the fracture envelope:
;time t l t l t l t l t l t l t l
0.00 0.0 0 0.15 0.3 0.3 0.5 0.5 1.0 0.65 0.5 0.80 0.3 1.0 0
8.00 0.0 0 0.15 0.3 0.3 0.5 0.5 1.0 0.65 0.5 0.80 0.3 1.0 0
The first value is the time within the soundfile for the envelope to begin. (As you can see, both lines have the same values: not very adventurous!)
You then need 7 pairs of time-within-the envelope, and level-for-that-time, labelled t and l above. So we have an envelope stretched over 1" starting and ending at level 0 (they must start at 0), rising to full level 1/2-way (t 0.5, l 1.0), then decaying again. I would guess that if the envelope was spread out so that the last t overlaps the time value on the next line, it would be rejected, but I don't know.
Anyway, the above works, even if a bit basic. I'm sure you'll be able to make more interesting changes!
(BTW, I can't guarantee the comment line ;time etc. I just put it here to show the structure of the file)
