diff --git a/level.py b/level.py
index 3fd58e0..9f3dea7 100644
--- a/level.py
+++ b/level.py
@@ -4,12 +4,18 @@ Created on Jul 22, 2011
 @author: Rio
 '''
 
+import blockrotation
 from box import BoundingBox
+from collections import defaultdict
+from entity import Entity, TileEntity
 import itertools
 from logging import getLogger
-from mclevelbase import *
-from collections import defaultdict
 import materials
+from math import floor
+from mclevelbase import ChunkMalformed, ChunkNotPresent, exhaust
+import nbt
+from numpy import argmax, swapaxes, zeros, zeros_like
+import os.path
 
 log = getLogger(__name__)
 warn, error, info, debug = log.warn, log.error, log.info, log.debug
@@ -127,7 +133,7 @@ class MCLevel(object):
     ### common to Creative, Survival and Indev. these routines assume
     ### self has Width, Height, Length, and Blocks
 
-    materials = classicMaterials
+    materials = materials.classicMaterials
     isInfinite = False
 
     compressedTag = None
@@ -273,7 +279,7 @@ class MCLevel(object):
 
         f.Entities, f.TileEntities = self._getFakeChunkEntities(cx, cz)
 
-        f.root_tag = TAG_Compound()
+        f.root_tag = nbt.TAG_Compound()
 
         return f
 
@@ -416,7 +422,7 @@ class MCLevel(object):
         blocks = self.Blocks[slices[0], slices[2], slices[1]]
         if len(blocksToReplace):
             blocktable = self.blockReplaceTable(blocksToReplace)
-            shouldRetainData = (self.materials == alphaMaterials) and all([blockrotation.SameRotationType(blockInfo, b) for b in blocksToReplace])
+            shouldRetainData = (self.materials == materials.alphaMaterials) and all([blockrotation.SameRotationType(blockInfo, b) for b in blocksToReplace])
 
             if hasattr(self, "Data") and shouldRetainData:
                 data = self.Data[slices[0], slices[2], slices[1]]
@@ -741,7 +747,7 @@ class EntityLevel(MCLevel):
             self.addEntity(e)
 
     def addEntity(self, entityTag):
-        assert isinstance(entityTag, TAG_Compound)
+        assert isinstance(entityTag, nbt.TAG_Compound)
         self.Entities.append(entityTag)
         self._fakeEntities = None
 
@@ -759,7 +765,7 @@ class EntityLevel(MCLevel):
         return entities[0]
 
     def addTileEntity(self, tileEntityTag):
-        assert isinstance(tileEntityTag, TAG_Compound)
+        assert isinstance(tileEntityTag, nbt.TAG_Compound)
 
         def differentPosition(a):
 
diff --git a/tests.py b/tests.py
index 58f9ea1..b1ee12b 100644
--- a/tests.py
+++ b/tests.py
@@ -12,6 +12,7 @@ try:
 except ImportError:
     from __init__ import *
 
+from cStringIO import StringIO
 import itertools
 import unittest
 import tempfile
@@ -88,21 +89,21 @@ class TestNBT(unittest.TestCase):
         "Create an indev level."
 
         "The root of an NBT file is always a TAG_Compound."
-        level = TAG_Compound(name="MinecraftLevel")
+        level = nbt.TAG_Compound(name="MinecraftLevel")
 
         "Subtags of a TAG_Compound are automatically named when you use the [] operator."
-        level["About"] = TAG_Compound()
-        level["About"]["Author"] = TAG_String("codewarrior")
+        level["About"] = nbt.TAG_Compound()
+        level["About"]["Author"] = nbt.TAG_String("codewarrior")
 
-        level["Environment"] = TAG_Compound()
-        level["Environment"]["SkyBrightness"] = TAG_Byte(16)
-        level["Environment"]["SurroundingWaterHeight"] = TAG_Short(32)
+        level["Environment"] = nbt.TAG_Compound()
+        level["Environment"]["SkyBrightness"] = nbt.TAG_Byte(16)
+        level["Environment"]["SurroundingWaterHeight"] = nbt.TAG_Short(32)
 
         "You can also create and name a tag before adding it to the compound."
-        spawn = TAG_List((TAG_Short(100), TAG_Short(45), TAG_Short(55)))
+        spawn = nbt.TAG_List((nbt.TAG_Short(100), nbt.TAG_Short(45), nbt.TAG_Short(55)))
         spawn.name = "Spawn"
 
-        mapTag = TAG_Compound()
+        mapTag = nbt.TAG_Compound()
         mapTag.add(spawn)
         mapTag.name = "Map"
         level.add(mapTag)
@@ -110,13 +111,13 @@ class TestNBT(unittest.TestCase):
         "I think it looks more familiar with [] syntax."
 
         l, w, h = 128, 128, 128
-        mapTag["Height"] = TAG_Short(h)  # y dimension
-        mapTag["Length"] = TAG_Short(l)  # z dimension
-        mapTag["Width"] = TAG_Short(w)  # x dimension
+        mapTag["Height"] = nbt.TAG_Short(h)  # y dimension
+        mapTag["Length"] = nbt.TAG_Short(l)  # z dimension
+        mapTag["Width"] = nbt.TAG_Short(w)  # x dimension
 
         "Byte arrays are stored as numpy.uint8 arrays. "
 
-        mapTag["Blocks"] = TAG_Byte_Array()
+        mapTag["Blocks"] = nbt.TAG_Byte_Array()
         mapTag["Blocks"].value = zeros(l * w * h, dtype=uint8)  # create lots of air!
 
         "The blocks array is indexed (y,z,x) for indev levels, so reshape the blocks"
@@ -127,7 +128,7 @@ class TestNBT(unittest.TestCase):
 
         "This is a great way to learn the power of numpy array slicing and indexing."
 
-        mapTag["Data"] = TAG_Byte_Array()
+        mapTag["Data"] = nbt.TAG_Byte_Array()
         mapTag["Data"].value = zeros(l * w * h, dtype=uint8)
 
         return level
@@ -136,7 +137,7 @@ class TestNBT(unittest.TestCase):
         level = self.testCreate()
 
         "Most of the value types work as expected. Here, we replace the entire tag with a TAG_String"
-        level["About"]["Author"] = TAG_String("YARRR~!")
+        level["About"]["Author"] = nbt.TAG_String("YARRR~!")
 
         "Because the tag type usually doesn't change, "
         "we can replace the string tag's value instead of replacing the entire tag."