diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7940678ef6..f1b53b410b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -39,7 +39,7 @@ set(CMAKE_CXX_FLAGS "${_PXR_CXX_FLAGS} ${CMAKE_CXX_FLAGS}")
 
 if(PXR_ENABLE_JS_SUPPORT)
     # Add EMSCRIPTEN specific compiler flags (is this the right place)?
-    set(EMSCRIPTEN_COMPILE_FLAGS "-s ALLOW_MEMORY_GROWTH=1 -s MAXIMUM_MEMORY=4GB -s ASSERTIONS=1 -s USE_PTHREADS=1 -s PTHREAD_POOL_SIZE=2 -s MODULARIZE=1 -s EXPORT_NAME='getUsdModule' -s 'EXTRA_EXPORTED_RUNTIME_METHODS=[\"FS\"]' -s FORCE_FILESYSTEM=1 -lidbfs.js")
+    set(EMSCRIPTEN_COMPILE_FLAGS "-s ALLOW_MEMORY_GROWTH=1 -s MAXIMUM_MEMORY=4GB -s ASSERTIONS=1 -s DISABLE_EXCEPTION_CATCHING=0 -s USE_PTHREADS=1 -s PTHREAD_POOL_SIZE=2 -s MODULARIZE=1 -s EXPORT_NAME='getUsdModule' -s 'EXTRA_EXPORTED_RUNTIME_METHODS=[\"FS\"]' -s FORCE_FILESYSTEM=1 --pre-js ${CMAKE_SOURCE_DIR}/js/prejs.js")
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${EMSCRIPTEN_COMPILE_FLAGS}")
     set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${EMSCRIPTEN_COMPILE_FLAGS}")
 
diff --git a/pxr/usdImaging/hdEmscripten/js/ThreeJsRenderDelegate.js b/pxr/usdImaging/hdEmscripten/js/ThreeJsRenderDelegate.js
index c712bc8f26..a573053207 100644
--- a/pxr/usdImaging/hdEmscripten/js/ThreeJsRenderDelegate.js
+++ b/pxr/usdImaging/hdEmscripten/js/ThreeJsRenderDelegate.js
@@ -77,10 +77,13 @@ class HydraMesh {
 
     const material = new THREE.MeshPhysicalMaterial( {
       side: THREE.DoubleSide,
-      color: new THREE.Color(0x00ff00) // a green color to indicate a missing material
-    } );
+      color: new THREE.Color(0xa0a0a0) // a gray default color      
+    });
 
     this._mesh = new THREE.Mesh( this._geometry, material );
+    this._mesh.castShadow = true;
+    this._mesh.receiveShadow = true;
+
     window.scene.add(this._mesh); // FIXME
   }
 
@@ -254,7 +257,7 @@ class HydraMaterial {
     if (!defaultMaterial) {
       defaultMaterial = new THREE.MeshPhysicalMaterial({
         side: THREE.DoubleSide,
-        color: new THREE.Color(0xff2997), // a bright pink color to indicate a missing material
+        color: new THREE.Color(0xa0a0a0), // a gray default color
         envMap: window.envMap,
       });
     }
@@ -310,6 +313,9 @@ class HydraMaterial {
         const clonedTexture = texture.clone();
         clonedTexture.format = HydraMaterial.channelMap[channel];
         clonedTexture.needsUpdate = true;
+        clonedTexture.wrapS = THREE.RepeatWrapping;
+        clonedTexture.wrapT = THREE.RepeatWrapping;
+
         this._material[materialParameterMapName] = clonedTexture;
 
         this._material.needsUpdate = true;