Fragment Shader not applyable at runtime?

I have the following scenrario: A Script generates ShaderCode and it is assigned to a virtual Material. The ShaderCode contains a fragment Shader and is working, if I put the Code into a .shader file and assign it to a created Material file.

If I try to assign the pure Code as a string to a new Material (Material m = new Material(Code)), the compiler produces:

Shader error in 'mcfShaders/Diffuse': Parse error: syntax error at line 15

So something is wrong with the CGPROGRAM. Maybe the Mapping in vertexInput or fragmentInput? This errormessage is not really helping...

 Shader "mcfShaders/Diffuse" {
   Properties {
      _Color ("Main Color", Color) = (1,1,1,1)
   }
   SubShader {
     Tags { "RenderType"="Transparent" "Queue"="Transparent" "LightMode"="ForwardBase" }
 
     LOD 200
     ZWrite On
     Lighting On
     Blend SrcAlpha OneMinusSrcAlpha
     Cull Back
 
     Pass {
       CGPROGRAM
       #pragma exclude_renderers ps3 xbox360 flash
       #pragma fragmentoption ARB_precision_hint_fastest
       #pragma vertex vert addshadow fullforwardshadows
       #pragma fragment frag
 
       uniform float4 _Color;
 
       struct vertInput {
         float4 vertex : POSITION;
         float4 color : COLOR;
       };
 
       struct fragInput {
         float4 pos : SV_POSITION;
         float4 diff : COLOR0;
       };
 
       fragInput vert(vertInput i) {
         fragInput r;
         r.pos = mul(UNITY_MATRIX_MVP, i.vertex);
         r.diff = _Color;
         return r;
       }
 
       half4 frag( fragInput i ) : COLOR {
         return half4(i.diff);
       }
       ENDCG
     }
   }
   Fallback "Diffuse"
 }

Hope someone with knowledge finds this :)