Okay, it's still too chilly out for yard work so here it goes:
First thing is to find the Classic decal you want to use: The Game Creators\FPS Creator\Files\gamecore\decals\
I used the fire decal. It's pretty big, but there are two smaller ones. If you're putting it in a barrel, try one of those!
The decal is a 16 frame sprite sheet. The one in GG is 64 frame. I didn't try just using the 16 frame sprite. It may or may not work. Might be worth a try, though. I copied and pasted the 16 frames from the Classic decal into a 2048x2048 image 4 times to make it 64 frames.
Open the GG directory for particles: Steam\steamapps\common\Game Guru\Files\effectbank\particles\.
Rename the 64smoke2.dds to something else. I called mine 64smoke2(1).dds (Just my renaming convention when I am preserving originals).
Save your newly created sprite sheet in the Guru particle directory as 64smoke2.dds
Now from this point you have some options that you will have to figure out for yourself. I did the quick and easy method.
I simply placed a trigger zone and assigned it's script to particlesinzone.lua
I increased the zone size, launched and walked into the zone and voila! FIRE! Note: The fire will display where the "target" is in the zone, and you can move this target outside the zone while in the property editor.
That's pretty much it, good luck!
EDIT: The 16 frame sprite sheet does work in GG particles, so you can skip the image editing step! Please make sure to preserve the original particle sprite sheet, though!
UPDATE: After further messing around with this, it appears GG doesn't like all the sprite sheets from Classic. I tried the mushroom sheet, and GG wouldn't even start! Do these at your own risk, and make note of which ones are failing please! It also appears that GG just grabs the first image in the folder regardless of the name. I could be wrong, but so far it seems that way!
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