Shader errors in Windows build ( renders black ) but not in Editor

We're currently using some shaders created with Shader Forge for our project.

Everything appears to work just fine when playing in the editor, but when we make a build, most of the shaders fail and a lot of black is the result.

During building this error is reported for many of the shaders:

Shader error in 'Shader Forge/shaderName': variable 'd' used without having been completely initialized at line 117 (on d3d11)

This alludes to the following line of shader code:

UnityGI gi = UnityGlobalIllumination(d, 1, normalDirection, ugls_en_data );

and in the output_log from the build as it's executed:

WARNING: Shader Unsupported: 'Shader Forge/shaderName' - Pass 'FORWARD' has no fragment shader WARNING: Shader Unsupported: 'Shader Forge/shaderName' - Pass 'FORWARD_DELTA' has no vertex shader WARNING: Shader Unsupported: 'Shader Forge/shaderName' - All passes removed

Here is the shader code which documents the lifetime of that crazy 'd' variable up until its moment of shame:

 /////// GI Data:
                 UnityLight light;
                 #ifdef LIGHTMAP_OFF
                     light.color = lightColor;
                     light.dir = lightDirection;
                     light.ndotl = LambertTerm (normalDirection, light.dir);
                 #else
                     light.color = half3(0.f, 0.f, 0.f);
                     light.ndotl = 0.0f;
                     light.dir = half3(0.f, 0.f, 0.f);
                 #endif
                 UnityGIInput d;
                 d.light = light;
                 d.worldPos = i.posWorld.xyz;
                 d.worldViewDir = viewDirection;
                 d.atten = attenuation;
                 d.boxMax[0] = unity_SpecCube0_BoxMax;
                 d.boxMin[0] = unity_SpecCube0_BoxMin;
                 d.probePosition[0] = unity_SpecCube0_ProbePosition;
                 d.probeHDR[0] = unity_SpecCube0_HDR;
                 d.boxMax[1] = unity_SpecCube1_BoxMax;
                 d.boxMin[1] = unity_SpecCube1_BoxMin;
                 d.probePosition[1] = unity_SpecCube1_ProbePosition;
                 d.probeHDR[1] = unity_SpecCube1_HDR;
                 Unity_GlossyEnvironmentData ugls_en_data;
                 ugls_en_data.roughness = 1.0 - gloss;
                 ugls_en_data.reflUVW = viewReflectDirection;
                 UnityGI gi = UnityGlobalIllumination(d, 1, normalDirection, ugls_en_data );
                 lightDirection = gi.light.dir;
                 lightColor = gi.light.color;

Is anyone able to suggest a place to start digging which will may unearth the root of the issue we're experiencing here?

Windows Version 8.1 Unity Version 5.3.1f1 Personal Shaderforge Version 1.2.6 Video Card Geforce GTX 980 TI

Many thanks as always.