Fixing Volcano smoke?

A thing thats bugged me since before RTW came out & someone pointed it out in discussion of a movie is that the smoke from volcanoes as seen in the battle maps is too fast moving.

I finally managed to find (what I presume is) the relevant section:
data\descr_particle.txt

Code:

---

type                        volcano_smoke
action                        advance
action                        age_to_limit
action                        expand, 100.0
action                        max_particles, 8000
renderer                quad_fade, 0.15, 0.7, 1
renderer_class        far
anim                        1, 0, do_not_loop
texture                        data/battlefield/cloud_sprite2.tga
texture_frame        0,1, 1,1, 1,0, 0,0

---

But I don't have the faintest idea about what would need to be changed to slow the animation.

Can anyone suggest/make the fix?
Or has it already been done & I just don't know it...

I'd suggest backing up descr_particle.txt first and then tweaking the odd value ie.

change action expand, 100.0 to 20.0

if it doesn't work just restore your backed up file and try something else
and see what happens. I don't think anyone has tried editting this file much.

No cigar.

Tried a bunch of variations & attempted to work out what the header stuff means but I don't get it & nothing seemed to change anything.

Anyone else got ideas?