diff --git a/build_visual_studio_vr_pybullet_double_cmake.bat b/build_visual_studio_vr_pybullet_double_cmake.bat
index 32cd01735..aaa1f9cc1 100644
--- a/build_visual_studio_vr_pybullet_double_cmake.bat
+++ b/build_visual_studio_vr_pybullet_double_cmake.bat
@@ -1,4 +1,4 @@
 mkdir build_cmake
 cd build_cmake
-cmake -DBUILD_PYBULLET=ON -DUSE_DOUBLE_PRECISION=ON -DCMAKE_BUILD_TYPE=Release -DPYTHON_INCLUDE_DIR=c:\python-3.5.3.amd64\include -DPYTHON_LIBRARY=c:\python-3.5.3.amd64\libs\python35.lib -DPYTHON_DEBUG_LIBRARY=c:\python-3.5.3.amd64\libs\python35_d.lib -G "Visual Studio 16 2019" ..
+cmake -DBUILD_PYBULLET=ON -DUSE_DOUBLE_PRECISION=ON -DCMAKE_BUILD_TYPE=Release -DPYTHON_INCLUDE_DIR=c:\python38\include -DPYTHON_LIBRARY=c:\python38\libs\python38.lib -DPYTHON_DEBUG_LIBRARY=c:\python38\libs\python38.lib -G "Visual Studio 16 2019" ..
 start .
\ No newline at end of file
diff --git a/examples/SharedMemory/PhysicsServerCommandProcessor.cpp b/examples/SharedMemory/PhysicsServerCommandProcessor.cpp
index ff3ec7db0..fbf1b2a37 100644
--- a/examples/SharedMemory/PhysicsServerCommandProcessor.cpp
+++ b/examples/SharedMemory/PhysicsServerCommandProcessor.cpp
@@ -2771,6 +2771,9 @@ void PhysicsServerCommandProcessor::createEmptyDynamicsWorld(int flags)
 #endif
 	}
 
+	 //may help improve run-time performance for many sleeping objects
+	m_data->m_dynamicsWorld->setForceUpdateAllAabbs(false);
+
 	//Workaround: in a VR application, where we avoid synchronizing between GFX/Physics threads, we don't want to resize this array, so pre-allocate it
 	m_data->m_dynamicsWorld->getCollisionObjectArray().reserve(128 * 1024);
 
diff --git a/examples/pybullet/gym/pybullet_data/toys/LICENSE.txt b/examples/pybullet/gym/pybullet_data/toys/LICENSE
similarity index 100%
rename from examples/pybullet/gym/pybullet_data/toys/LICENSE.txt
rename to examples/pybullet/gym/pybullet_data/toys/LICENSE
diff --git a/src/BulletDynamics/Featherstone/btMultiBodyDynamicsWorld.cpp b/src/BulletDynamics/Featherstone/btMultiBodyDynamicsWorld.cpp
index fef95f0c4..9f304929c 100644
--- a/src/BulletDynamics/Featherstone/btMultiBodyDynamicsWorld.cpp
+++ b/src/BulletDynamics/Featherstone/btMultiBodyDynamicsWorld.cpp
@@ -137,7 +137,14 @@ void btMultiBodyDynamicsWorld::updateActivationState(btScalar timeStep)
 				btMultiBodyLinkCollider* col = body->getBaseCollider();
 				if (col && col->getActivationState() == ACTIVE_TAG)
 				{
-					col->setActivationState(WANTS_DEACTIVATION);
+                    if (body->hasFixedBase())
+					{
+                        col->setActivationState(ISLAND_SLEEPING);
+                    } else
+					{
+                        col->setActivationState(WANTS_DEACTIVATION);
+                    }
+					
 					col->setDeactivationTime(0.f);
 				}
 				for (int b = 0; b < body->getNumLinks(); b++)