Ed,
As Dave says, use a navigation light from the [lights] section in place of your effect name in the [smokesystem] section. Here's an example to best show what I mean. I've got 2 dedicated smoke effects for a DC-10 (a and b), as the engines are on different levels - wings and tail. This is what the [smokesystem] entry in my aircraft.cfg looks like:
[SMOKESYSTEM]
smoke.0=-8.4,-10.0,-27.6, fx_dc10aexhaust.fx
smoke.1=14.4,-100.0,0.0, fx_dc10bexhaust.fx
smoke.2=-8.4,-10.0,27.6, fx_dc10aexhaust.fx
So smoke.1 is on the centreline way behind the other 2 engines. Even though I've put figures in for the first value (vertical), they have no effect in the sim. So use Windows Notepad to open your selected .fx file (it's just a standard .txt file with the filetype renamed .fx) and you'll see sectioned commands, just like in aircraft.cfg. For each particle comprising the effect, there are emitter, particle and particle attributes section. Here is the parameter you need to change:
[Emitter.0]
Lifetime=0.00, 0.00
Delay=0.00, 0.00
Bounce=0.00
Rate=30.00, 40.00
X Emitter Velocity=0.00, 0.00
Y Emitter Velocity=0.00, 0.00
Z Emitter Velocity=0.00, 0.00
Drag=0.00, 0.00
X Particle Velocity=0.00, 0.00
Y Particle Velocity=0.00, 0.00
Z Particle Velocity=-20.00, -20.00
X Rotation=0.00, 0.00
Y Rotation=0.00, 0.00
Z Rotation=0.00, 0.00
X Offset=0.00, 0.00
Y Offset=7.00, 7.00 //Change this one. +=up, -=down
Z Offset=0.00, 0.00
For more details, look at the Microsoft special effects SDK.
By the way, when you save the .fx file after modifying it, make sure that you include the whole name including the filetype (e.g. effect.fx), or else Notepad will save it as a .txt file.
Good luck!
