Anim8or Community

Hey all
I was trying to figure out a script by Tyson Collins (AKA Null) and I was wondering if someone could explain to me some of the things Here's the script I added some questions which are blue. One last thing where does it say in the script which points are where.

#plugin("object", "mesh", "plane"); I understand this it's the name and type
#parameter("side", float, 10.0, 0.001, 99999, scale);this parameter are mouse rules for the shape 1st is name for the dialog 2nd parameters is type of counter used 3rd is default/start scale 4th is min scale 5th max scale and last parameter tells animator to scale object
optional 7th can be added to locked to x,y or z scale per viewpoint when using non-unform scale tool by adding for example edit line "scale,scale_y);" at the end
#return($plane); this declares the object
#button(17, 25, 2,
    0x00000000, 0x00000000, 0x0fffffff, 0x00010001,
    0x00010001, 0x00010001, 0x00010001, 0x00010001,
    0x00010001, 0x00010001, 0x00010001, 0x00010001,
    0x00010001, 0x00010001, 0x00010001, 0x00010001,
    0x00010001, 0x00010001, 0x0fffffff, 0x00000000,
    0x00000000, 0x00000000, 0x00000000, 0x00000000,
    0x00000000);
shape $plane;   these are the elements/counters used in the script
int $side,$i;
point3 $p;
$side = parameter("side");

$plane.Open();
$plane.OpenFace(0,4);
TextCoord are the U,V texture coordinates fixed to the point textcoord must be set before the point is drawn
$p.x = -$side;
$p.y = 0;
$p.z = -$side;
$plane.TexCoordN($plane.AddTexCoord((0,1)));
$plane.VertexN($plane.AddPoint($p));

$p.x = $side;
$p.y = 0;
$p.z = -$side;
$plane.TexCoordN($plane.AddTexCoord((1,1)));
$plane.VertexN($plane.AddPoint($p));

$p.x = $side;
$p.y = 0;
$p.z = $side;
$plane.TexCoordN($plane.AddTexCoord((1,0)));
$plane.VertexN($plane.AddPoint($p));

$p.x = -$side;
$p.y = 0;
$p.z = $side;
$plane.TexCoordN($plane.AddTexCoord((0,0)));
$plane.VertexN($plane.AddPoint($p));

$plane.CloseFace();
$plane.Close();

If someone could please help me I would really appreciate it. Thanks