Problem with my custom shader

I'm a student and we have to port a shader from render monkey into unity's shader lab and I would someone to look over it if that's not too much trouble. It's not working and when I moved the GLSLPROGRAM of the program to the top it suddenly said my laptop couldn't play it although it plays the shader on render monkey.

GLSLPROGRAM
Shader "Sub_Surface_Shader"
{
Properties {
_Color ("Base Color", Color) = (1,1,1,1)
_SpecColor("Spec Color", Color) = (1, 1, 1, 1)
}

}

#pragma vertex vert
#pragma fragment frag
#pragma multi_compile_builtin
#pragma fragmentoption ARB_fog_exp2
#pragma fragmentoption ARB_precision_hint_fastest
#ifdef VERTEX

// Set light-position

uniform vec3 LightPosition;

// Varying variables to be sent to Fragment Shader

varying vec3 worldNormal, eyeVec, lightVec, vertPos, lightPos;



void subScatterVS(in vec4 ecVert)

{

lightVec = LightPosition - ecVert.xyz;

eyeVec = -ecVert.xyz;

vertPos = ecVert.xyz;

lightPos = LightPosition;

}

void main()
{
worldNormal = gl_NormalMatrix * gl_Normal;

vec4 ecPos = gl_ModelViewProjectionMatrix * gl_Vertex;

// Call function to set varyings for subscatter FS
subScatterVS(ecPos);

//Transform vertex by modelview and projection matrices

gl_Position = ecPos;

//Forward current texture coordinates after applying texture matrix

gl_TexCoord[0] = gl_TextureMatrix[0] * gl_MultiTexCoord0;
}
#endif
TRANSFER_VERTEX_TO_FRAGMENT(o);

// Variables for lighting properties
#ifdef FRAGMENT
#include "AutoLight.glslinc"
#include "UnityCG.glslinc"
uniform float MaterialThickness;

uniform vec3 ExtinctionCoefficient; // Will show as X Y and Z ports in QC, but actually represent RGB values.

uniform vec4 LightColor;

uniform vec4 BaseColor;

uniform vec4 SpecColor;

uniform float SpecPower;

uniform float RimScalar;

// Varying variables to be sent to Fragment Shader

varying vec3 worldNormal, eyeVec, lightVec, vertPos, lightPos;

float halfLambert(in vec3 vect1, in vec3 vect2)
{
float product = dot(vect1,vect2);
return product * 0.5 + 0.5;
}

float blinnPhongSpecular(in vec3 normalVec, in vec3 lightVec, in float specPower)

{

vec3 halfAngle = normalize(normalVec + lightVec);

return pow(clamp(0.0,1.0,dot(normalVec,halfAngle)),specPower);

}

// Main fake sub-surface scatter lighting function

vec4 subScatterFS()

{

float attenuation = 10.0 * (1.0 / distance(lightPos,vertPos));

vec3 eVec = normalize(eyeVec);

vec3 lVec = normalize(lightVec);

vec3 wNorm = normalize(worldNormal);



vec4 dotLN = vec4(halfLambert(lVec,wNorm) * attenuation);

//dotLN *= texture2D(Texture, gl_TexCoord[0].xy);

dotLN *= BaseColor;



vec3 indirectLightComponent = vec3(MaterialThickness * max(0.0,dot(-wNorm,lVec)));

indirectLightComponent += MaterialThickness * halfLambert(-eVec,lVec);

indirectLightComponent *= attenuation;

indirectLightComponent.r *= ExtinctionCoefficient.r;

indirectLightComponent.g *= ExtinctionCoefficient.g;

indirectLightComponent.b *= ExtinctionCoefficient.b;



vec3 rim = vec3(1.0 - max(0.0,dot(wNorm,eVec)));

rim *= rim;

rim *= max(0.0,dot(wNorm,lVec)) * SpecColor.rgb;



vec4 finalCol = dotLN + vec4(indirectLightComponent,1.0);

finalCol.rgb += (rim * RimScalar * attenuation * finalCol.a);

finalCol.rgb += vec3(blinnPhongSpecular(wNorm,lVec,SpecPower) * attenuation * SpecColor * finalCol.a * 0.05);

finalCol.rgb *= LightColor.rgb;
return finalCol;
}
void main()
{
gl_FragColor = subScatterFS();
}
#endif
}
ENDGLSL

 

check the docs: Reference Manual > ShaderLab Reference > Writing shader programs > GLSL Shader Programs

and this thread: http://forum.unity3d.com/threads/39629-GLSL-shader
for an example GLSL shader.