Invalid input in Matrix multiply
UnityEngine.Debug:LogError(Object)
ShaderForge.SFNCG_MatrixMultiply:Refresh()
ShaderForge.SF_NodeConnector:LinkTo(SF_NodeConnector, LinkingMethod, Boolean)
ShaderForge.SF_Link:Establish(SF_Editor, LinkingMethod)
ShaderForge.SF_Parser:LoadFromNodeData(String, Single, String&)
ShaderForge.SF_Parser:ParseNodeDataFromShader(SF_Editor, Shader)
ShaderForge.SF_Editor:InitializeInstance(Shader)
ShaderForge.SF_Editor:Init(Shader)
UnityEditor.DockArea:OnGUI()

This problem still persists since Version 1.18 (at least). It's annoying and makes debugging shaders definitely more complicated than it should be. Currently, I'm on Unity 5.2.5 with shader forge 1.25.