The video below shows you a step by step guide on how to make a particle stream that resembles fire. It is about 30 minutes long.

This is the image used in the video so you can follow along

test64.png

To save it on your computer, just right-click and select "save image as..." 

Save it to the project folder by clicking the icon and drag and drop.

One thing to remember when working in the debug panel is that you should not click on anything. This first value you input must be at the base level and not chained off of any other rule. Unfortunately, once you click on something, you can't unclick.

When you are done imputing all of your values, your panel should look like this:

Below are all of the values used in this tutorial. When you are adding new keys and data, remember to have the correct parent clicked. For example in the list below ParitcleEffect is the parent and BlendMode, Gravity, ParticleRule0, ParticleRule1, ParticleRule2, and TextureFilename are all children of that parent. 

(key)ParticleEffect
    (data)BlendMode Additive
    (data)Gravity    0,0,3
    (key)ParticleRule0
        (key)Position
            (data)Bottom 0,0,0
            (data)InnerRadius 0
            (data)OuterRadius .5
            (data)Top 0,0,1
            (data)Type Cone
        (data)Rate 200
        (data)Type Source
        (key)Velocity
            (data)Bottom 0,0,-.5
            (data)InnerRadius 0
            (data)OuterRadius 0
            (data)Top 0,0,0
            (data)Type Cone
    (key)ParticleRule1
        (data)AgeLimit 1
        (data)Type KillOld
    (key)ParticleRule2
        (data)Alpha 0
        (data)Color 255,216,61
        (data)Scale .003
        (data)Type TargetColor
    (data)TextureFilename test64yellow.png

These are the available particle shapes used for both the Position key and the Velocity key.

    Box: Takes two positions: these two positions are
    opposing corners of the box.

        BottomCorner 0,0,0
        TopCorner 0,0,0
        Type Box

    Cone: Takes two positions: the "top" is the pointy
    end of the cone, and the "bottom" is the blunt end.
    The Inner and Outer radius are the radii of the blunt
    end. (a nonzero inner radius produces a hollow cone)

        Bottom 0,0,0
        InnerRadius 0
        OuterRadius 0
        Top 0,0,0
        Type Cone

    Cylinder: Takes two positions which are endpoints
    of the cylinder. Inner and outer radius work in the
    same way as they do for cones and spheres.

        Bottom 0,0,0
        InnerRadius 0
        OuterRadius 0
        Top 0,0,0
        Type Cylinder

    Disc: Takes a centre point of the disc, a normal
    vector which points away from the disc, and two radii
    scalars.

        InnerRadius 0
        Normal 0,0,0
        OuterRadius 0
        Position 0,0,0
        Type Disc

    Line: Takes two positions: the endpoints of the line.

        End 0,0,0
        Start 0,0,0
        Type Line

    Plane: An infinitely large, flat plane.

        Normal 0,0,0
        Position 0,0,0
        Type Plane

    Point: A single geometric point.

        Position 0,0,0
        Type Point

    Rectangle: A rhomboid plane. Takes a center point,
    and two vectors that determine the center points of
    the sides.

        Position 0,0,0
        Type Rectangle
        u 0,0,0
        v 0,0,0

    Sphere: Takes a position that is the center of the
    sphere, plus an inner and outer radius. If the inner
    radius is nonzero, then the sphere is hollow.

        InnerRadius 0
        OuterRadius 0
        Position 0,0,0
        Type Sphere

    Triangle: A simple triangle. Takes three positions
    that are the corners of the triangle.

        CornerA 0,0,0
        CornerB 0,0,0
        CornerC 0,0,0
        Type Triangle

These are the additional particle rules to refine your particles speed, direction, and color.

    Sink: Particles that come into contact with a
    Sink are destroyed. The domain* describes the
    shape of the sink.

        SinkDomain
            BottomCorner 0,0,0
            TopCorner 0,0,0
            Type Box (example)
        Type Sink

    KillOld: Destroys particles whose age is above some
    number of seconds. The AgeLimit determines the distance
    the particle travels before disappearing. If you wish
    to fill a room with particles then leave the number
    high, but if you want them close to the origin point,
    reduce the AgeLimit to a lower number.

        AgeLimit 0
        Type KillOld

    RandomAccel: Add a random velocity vector from the
    domain given into each particle's velocity every frame.
    This makes the particles appear to wander around a bit
    instead of moving in parabolic arcs.

        Acceleration
            InnerRadius 0
            OuterRadius 0
            Position 0,0,0
            Type Sphere (example shape)
        Type RandomAccel

    RandomDisplace: Add a random displacement vector from
    the domain into each particle's position every frame.
    This makes particles appear to twitch.

        Displacement
            InnerRadius 0
            OuterRadius 0
            Position 0,0,0
            Type Sphere (example shape)
        Type RandomDisplace

    SpeedLimit: Describes minimum and maximum speeds for
    all particles.

        MaxSpeed 0
        MinSpeed 0
        Type SpeedLimit

    TargetVelocity: Every frame, adjust the velocity of
    all particles in the system to be closer to the
    velocity given. "Scale" is the percentage of the
    target velocity that is applied each second.

        Velocity 0
        Scale 0
        Type TargetVelocity

    TargetColor: Defines a target color. The actual
    color is chosen at random. The Color data uses the
    Decimal Code RGB values.

        Alpha 0
        Color 255,255,255
        Scale 0
        Type TargetColor

Sources:
     https://avatars.imvu.com/shop/includes/iframe_product_description.php?products_id=2225497
     https://web.archive.org/web/20190425110312/https://www.imvu.com/catalog/modules.php?op=modload&name=phpbb2&file=viewtopic.php&t=381581&postdays=0&postorder=asc&start=0
     http://www.imvumafias.org/community/viewtopic.php?f=157&t=11072