diff --git a/direct/src/p3d/Packager.py b/direct/src/p3d/Packager.py
index 8685de09ea..f478f4178d 100644
--- a/direct/src/p3d/Packager.py
+++ b/direct/src/p3d/Packager.py
@@ -3341,7 +3341,7 @@ class Packager:
         self.do_module('VFSImporter', filename = filename)
         self.do_freeze('_vfsimporter', compileToExe = False)
 
-        self.do_file('panda3d/core.pyd');
+        self.do_file('panda3d/_core.pyd');
 
         # Now that we're done freezing, explicitly add 'direct' to
         # counteract the previous explicit excludeModule().
diff --git a/direct/src/plugin/p3dPythonRun.cxx b/direct/src/plugin/p3dPythonRun.cxx
index 667f34e7dc..e3be05bfc8 100644
--- a/direct/src/plugin/p3dPythonRun.cxx
+++ b/direct/src/plugin/p3dPythonRun.cxx
@@ -236,29 +236,37 @@ run_python() {
   }
   Py_DECREF(app_runner_class);
 
+  // Import the JavaScript module.
+  PyObject *javascript_module = PyImport_ImportModule("direct.p3d.JavaScript");
+  if (javascript_module == NULL) {
+    nout << "Failed to import direct.p3d.JavaScript\n";
+    PyErr_Print();
+    return false;
+  }
+
   // Get the UndefinedObject class.
-  _undefined_object_class = PyObject_GetAttrString(app_runner_module, "UndefinedObject");
+  _undefined_object_class = PyObject_GetAttrString(javascript_module, "UndefinedObject");
   if (_undefined_object_class == NULL) {
     PyErr_Print();
     return false;
   }
 
   // And the "Undefined" instance.
-  _undefined = PyObject_GetAttrString(app_runner_module, "Undefined");
+  _undefined = PyObject_GetAttrString(javascript_module, "Undefined");
   if (_undefined == NULL) {
     PyErr_Print();
     return false;
   }
 
   // Get the ConcreteStruct class.
-  _concrete_struct_class = PyObject_GetAttrString(app_runner_module, "ConcreteStruct");
+  _concrete_struct_class = PyObject_GetAttrString(javascript_module, "ConcreteStruct");
   if (_concrete_struct_class == NULL) {
     PyErr_Print();
     return false;
   }
 
   // Get the BrowserObject class.
-  _browser_object_class = PyObject_GetAttrString(app_runner_module, "BrowserObject");
+  _browser_object_class = PyObject_GetAttrString(javascript_module, "BrowserObject");
   if (_browser_object_class == NULL) {
     PyErr_Print();
     return false;
@@ -272,7 +280,7 @@ run_python() {
   }
 
   Py_DECREF(app_runner_module);
-
+  Py_DECREF(javascript_module);
 
   // Construct a Python wrapper around our methods we need to expose to Python.
   static PyMethodDef p3dpython_methods[] = {
diff --git a/direct/src/showbase/VFSImporter.py b/direct/src/showbase/VFSImporter.py
index 6f8c76266f..1fc8c6796d 100644
--- a/direct/src/showbase/VFSImporter.py
+++ b/direct/src/showbase/VFSImporter.py
@@ -1,7 +1,7 @@
 __all__ = ['register', 'sharedPackages',
            'reloadSharedPackage', 'reloadSharedPackages']
 
-from panda3d.core import Filename, VirtualFileSystem, VirtualFileMountSystem, OFileStream, copyStream
+from panda3d._core import Filename, VirtualFileSystem, VirtualFileMountSystem, OFileStream, copyStream
 import sys
 import marshal
 import imp
diff --git a/direct/src/showutil/FreezeTool.py b/direct/src/showutil/FreezeTool.py
index df845b0c26..781caf9588 100644
--- a/direct/src/showutil/FreezeTool.py
+++ b/direct/src/showutil/FreezeTool.py
@@ -17,7 +17,6 @@ except ImportError:
     p3extend_frozen = None
 
 from panda3d.core import *
-from pandac.extension_native_helpers import dll_suffix, dll_ext
 
 # Check to see if we are running python_d, which implies we have a
 # debug build, and we have to build the module with debug options.
@@ -1394,15 +1393,6 @@ class PandaModuleFinder(modulefinder.ModuleFinder):
                 # It's a frozen module.
                 return (None, name, ('', '', imp.PY_FROZEN))
 
-        # Look for a dtool extension.  This loop is roughly lifted
-        # from extension_native_helpers.Dtool_PreloadDLL().
-        filename = name + dll_suffix + dll_ext
-        for dir in sys.path + [sys.prefix]:
-            lib = os.path.join(dir, filename)
-            if os.path.exists(lib):
-                file = open(lib, 'rb')
-                return (file, lib, (dll_ext, 'rb', imp.C_EXTENSION))
-
         message = "DLL loader cannot find %s." % (name)
         raise ImportError, message
 
diff --git a/makepanda/makepanda.py b/makepanda/makepanda.py
index 35bfea1e7f..30de3f1552 100755
--- a/makepanda/makepanda.py
+++ b/makepanda/makepanda.py
@@ -5026,11 +5026,13 @@ if (RTDIST or RUNTIME):
     TargetAdd('p3dpython.exe', input='p3dpython_p3dPythonMain.obj')
     TargetAdd('p3dpython.exe', input=COMMON_PANDA_LIBS)
     TargetAdd('p3dpython.exe', input='libp3tinyxml.ilb')
+    TargetAdd('p3dpython.exe', input='libp3interrogatedb.dll')
     TargetAdd('p3dpython.exe', opts=['PYTHON', 'WINUSER'])
 
     TargetAdd('libp3dpython.dll', input='p3dpython_p3dpython_composite1.obj')
     TargetAdd('libp3dpython.dll', input=COMMON_PANDA_LIBS)
     TargetAdd('libp3dpython.dll', input='libp3tinyxml.ilb')
+    TargetAdd('libp3dpython.dll', input='libp3interrogatedb.dll')
     TargetAdd('libp3dpython.dll', opts=['PYTHON', 'WINUSER'])
 
     if GetTarget() == 'windows':
@@ -5042,6 +5044,7 @@ if (RTDIST or RUNTIME):
       TargetAdd('p3dpythonw.exe', input='p3dpythonw_p3dPythonMain.obj')
       TargetAdd('p3dpythonw.exe', input=COMMON_PANDA_LIBS)
       TargetAdd('p3dpythonw.exe', input='libp3tinyxml.ilb')
+      TargetAdd('p3dpythonw.exe', input='libp3interrogatedb.dll')
       TargetAdd('p3dpythonw.exe', opts=['SUBSYSTEM:WINDOWS', 'PYTHON', 'WINUSER'])
 
   if (PkgSkip("OPENSSL")==0 and RTDIST):
diff --git a/panda/src/glstuff/glGraphicsStateGuardian_src.cxx b/panda/src/glstuff/glGraphicsStateGuardian_src.cxx
index 89227ee1bf..bfc5914b03 100644
--- a/panda/src/glstuff/glGraphicsStateGuardian_src.cxx
+++ b/panda/src/glstuff/glGraphicsStateGuardian_src.cxx
@@ -8799,6 +8799,7 @@ get_usage(Geom::UsageHint usage_hint) {
   return GL_STATIC_DRAW;
 }
 
+#ifndef NDEBUG
 ////////////////////////////////////////////////////////////////////
 //     Function: GLGraphicsStateGuardian::get_compressed_format_string
 //       Access: Public, Static
@@ -8917,6 +8918,7 @@ get_compressed_format_string(GLenum format) {
     return NULL;
   }
 }
+#endif
 
 ////////////////////////////////////////////////////////////////////
 //     Function: GLGraphicsStateGuardian::get_light_color