diff --git a/Gems/Atom/RPI/Code/Source/RPI.Edit/Material/LuaMaterialFunctorSourceData.cpp b/Gems/Atom/RPI/Code/Source/RPI.Edit/Material/LuaMaterialFunctorSourceData.cpp
index 37bd5a19f2..14ef3bb17d 100644
--- a/Gems/Atom/RPI/Code/Source/RPI.Edit/Material/LuaMaterialFunctorSourceData.cpp
+++ b/Gems/Atom/RPI/Code/Source/RPI.Edit/Material/LuaMaterialFunctorSourceData.cpp
@@ -137,7 +137,10 @@ namespace AZ
             }
             else if (!m_luaSourceFile.empty())
             {
-                auto loadOutcome = RPI::AssetUtils::LoadAsset<ScriptAsset>(materialTypeSourceFilePath, m_luaSourceFile, ScriptAsset::CompiledAssetSubId);
+                // The sub ID for script assets must be explicit.
+                // LUA source files output a compiled as well as an uncompiled asset, sub Ids of 1 and 2.
+                auto loadOutcome =
+                    RPI::AssetUtils::LoadAsset<ScriptAsset>(materialTypeSourceFilePath, m_luaSourceFile, ScriptAsset::CompiledAssetSubId);
                 if (!loadOutcome)
                 {
                     AZ_Error("LuaMaterialFunctorSourceData", false, "Could not load script file '%s'", m_luaSourceFile.c_str());
diff --git a/Gems/Atom/RPI/Code/Source/RPI.Edit/Material/MaterialSourceData.cpp b/Gems/Atom/RPI/Code/Source/RPI.Edit/Material/MaterialSourceData.cpp
index e5466a173f..d6308ec655 100644
--- a/Gems/Atom/RPI/Code/Source/RPI.Edit/Material/MaterialSourceData.cpp
+++ b/Gems/Atom/RPI/Code/Source/RPI.Edit/Material/MaterialSourceData.cpp
@@ -250,7 +250,7 @@ namespace AZ
                 const auto parentTypeAssetId = AssetUtils::MakeAssetId(parentSourceAbsPath, parentSourceData.m_materialType, 0);
                 if (!parentTypeAssetId)
                 {
-                    AZ_Error("MaterialSourceData", false, "Parent material asset ID isn't valid: '%s'.", parentSourceAbsPath.c_str());
+                    AZ_Error("MaterialSourceData", false, "Parent material asset ID wasn't found: '%s'.", parentSourceAbsPath.c_str());
                     return Failure();
                 }