Transparent Reflective

I found similar questions answered already, however what I like to implement is a little bit different.I want to create a transparent reflective shader where I can control the transparency + reflection with a texture (instead of a color value) Here's my shader,

Shader "myshader" { Properties { _MainTex ("Base (RGB) Trans (A)", 2D) = "white" {} _Cube ("Cubemap", CUBE) = "" {} } SubShader { Tags {"Queue"="transparent" "RenderType"="transparent" }

Cull Off

 CGPROGRAM
 #pragma surface surf Lambert alpha



 struct Input 
 {
     float3 worldRefl;
     float4 _MainTex;
 };

 samplerCUBE _Cube;
 float4 _MainTex;

 void surf (Input IN, inout SurfaceOutput o) {
     o.Albedo = _MainTex.rgb;
     o.Emission = texCUBE (_Cube, IN.worldRefl).rgb*_MainTex.a;
     o.Alpha = _MainTex.a;
 }
 ENDCG

} FallBack "Transparent/Diffuse"

}

which isn't working, no error messages though

ANY help greatly appreciated, Thank You!