diff --git a/build/codeblocks/timberAllocation.cbp b/build/codeblocks/timberAllocation.cbp
index f4ccd2d..91ff149 100644
--- a/build/codeblocks/timberAllocation.cbp
+++ b/build/codeblocks/timberAllocation.cbp
@@ -12,7 +12,7 @@
 				<Option object_output="obj/Debug/" />
 				<Option type="1" />
 				<Option compiler="gcc_v83" />
-				<Option parameters="../data/t3.txt" />
+				<Option parameters="../data/timber-alloc-data.txt" />
 				<Compiler>
 					<Add option="-g" />
 				</Compiler>
diff --git a/src/TimberAllocation.h b/src/TimberAllocation.h
index b9ca774..102bdd8 100644
--- a/src/TimberAllocation.h
+++ b/src/TimberAllocation.h
@@ -76,7 +76,7 @@ class cTimber : public cSpace
 
     void used( bool f = true )
     {
-        myUsed = true;
+        myUsed = f;
     }
     bool isUsed() const
     {
@@ -93,6 +93,15 @@ class cTimber : public cSpace
         return myLevel;
     }
 
+    void usedbyLevel( bool f )
+    {
+        myUsedbyLevel = f;
+    }
+    bool isUsedbyLevel()
+    {
+        return myUsedbyLevel;
+    }
+
     std::string myUserID;
     int myCount;
 
@@ -101,6 +110,7 @@ class cTimber : public cSpace
     timber_t myStock;   // if an allocated order, the stock allocated to
     bool myUsed;        // true if a stock that haveen used to cut orders
     int myLevel;         // the location of the top of the highest level cut
+    bool myUsedbyLevel;  // true if stock has been allocated to current level
 };
 
 class cInventory
@@ -153,14 +163,18 @@ class cLevel
 public:
     timberv_t myOrder;      // orders
     timber_t  myStock;      // stock allocated to level
-    int myAreaUsed;
 
     cLevel()
         : myAreaUsed( 0 )
     {
 
     }
-    void removePacked();    // remove orders that have been packed
+
+    /** remove orders that have been packed
+        @return 0: none packed, 1: some packed, 2: all packed
+    */
+    int removePacked();
+
     std::string text() const;
     int height() const
     {
@@ -174,10 +188,16 @@ class cLevel
     {
         myAreaUsed += order->myLength * order->myWidth;
     }
-    int wastage() const
-    {
-        return height() * ( myStock->myLength * myStock->myWidth - myAreaUsed );
-    }
+    /** Volume wasted when level cut from stock
+        @return volume wasted
+
+        This calculates wastage only for the currently stacked level
+        so this needs to be called for each stacked level
+    */
+    int wastage() const;
+
+private:
+    int myAreaUsed;
 };
 
 class cInstance
@@ -203,6 +223,14 @@ class cInstance
     */
     void expandCount();
 
+    /// Number of orders that could not fit
+    int unPackedCount() const
+    {
+        return (int)myUnpacked.size();
+    }
+
+    bool isEveryIDUnique();
+
     timberv_t myOrder;          /// the timbers that have to be delivered
 
     std::vector<std::pair<timber_t,timber_t>> myAllocation;
@@ -280,7 +308,7 @@ bool CS2LNW(
     cLevel& level, int h );
 
 /// Use pack2 engine to do 2D level cutting
-bool CS2Pack2(
+void CS2Pack2(
     cInstance& I,
     cLevel& level, int h );
 
@@ -300,11 +328,13 @@ void AllocateOrder(
 
 /** Record the V cut for a level in the instance
     @param[in] I the instance
-    @param[in] level
+    @param[in] stock
+    @param[in] h height for cut at top of level
 */
 void CutLevel(
     cInstance& I,
-    cLevel& level );
+    timber_t stock,
+    int h );
 
 void ReturnToInventory(
     cInventory& I );
diff --git a/src/taCutter.cpp b/src/taCutter.cpp
index 21b1a6c..c216008 100644
--- a/src/taCutter.cpp
+++ b/src/taCutter.cpp
@@ -65,6 +65,8 @@ void LevelsToStock(
     std::vector< cLevel >& levels,
     cInventory& inventory )
 {
+    for( timber_t t : inventory.myStock )
+        t->usedbyLevel( false );
     for ( auto& level : levels )
     {
         LevelToStock( I, level, inventory.myStock );
@@ -87,7 +89,11 @@ LevelToStock(
     bool found = false;
     for( timber_t t : stock )
     {
-        if( t->isUsed() )
+        // check if this stock was previously allocated to this level
+        // if so, it means that the level could not be packed into the stock
+        // probably because the W and/or length were too short
+        // in any case we do not want to allocate the stock again
+        if( t->isUsedbyLevel() )
             continue;
 
         int stockHeight = t->myHeight;
@@ -132,11 +138,15 @@ void LevelCuts(
     cInventory& inventory )
 {
     bool allPacked;
+
     // loop over levels
     for( cLevel& level : levels )
     {
         std::cout << "cutting level " << level.text() << "\n";
 
+        for( timber_t t : inventory.myStock )
+            t->usedbyLevel( false );
+
         do
         {
             /* stack levels
@@ -151,16 +161,20 @@ void LevelCuts(
                 h < level.myStock->myHeight;    // does stock have enough height to stack another level?
                 h += level.height() )           // up one level
             {
+
                 // Use 2D cutting algorithm to cut orders from level.
 
 #ifdef USE_CS2LNW
                 allPacked = CS2LNW( I, level, h );
 #endif // USE_CS2LNW
 #ifdef USE_CS2Pack2
-                allPacked = CS2Pack2( I, level, h );
+                CS2Pack2( I, level, h );
 #endif // CS2Pack2
 
-                if(  allPacked )
+                // remove packed timbers from level
+                int ret = level.removePacked();
+
+                if(  ret == 2 )
                 {
                     // all timbers in this level are packed
                     std::cout << "all timbers in this level are packed\n";
@@ -168,24 +182,33 @@ void LevelCuts(
                     break;
                 }
 
-                // remove timbers from level that have been packed
-                level.removePacked();
-
-                // TODO: return unused remainders to inventory
+                if( ret == 1 )
+                {
+                    // some packed
+                    continue;
+                }
 
-                if( ! allPacked )
+                if( ret == 0 )
                 {
-                    // stock timber exhausted, need to allocate another
-                    if( ! LevelToStock( I, level, inventory.myStock ) )
-                    {
-                        // no suitable stock available
-                        std::cout << " no suitable stock available\n";
-                        I.addUnpacked( level.myOrder );
-                        allPacked = true;
-                    }
+                    // nothing packed
+                    level.myStock->usedbyLevel( true );
+                    break;
                 }
 
+            }  // loop back to cut another level from the stock
+
+            if( ! allPacked )
+            {
+                // stock timber exhausted, need to allocate another
+                if( ! LevelToStock( I, level, inventory.myStock ) )
+                {
+                    // no suitable stock available
+                    std::cout << " no suitable stock available\n";
+                    I.addUnpacked( level.myOrder );
+                    return;
+                }
             }
+
         }
         while( ! allPacked );
     }
@@ -194,8 +217,6 @@ void LevelCuts(
         // success
         return;
     }
-
-
 }
 bool CS2LNW(
     cInstance& I,
@@ -245,7 +266,7 @@ bool CS2LNW(
     return allPacked;
 }
 
-bool CS2Pack2(
+void CS2Pack2(
     cInstance& I,
     cLevel& level, int h )
 {
@@ -295,7 +316,8 @@ bool CS2Pack2(
             */
             CutLevel(
                 I,
-                level );
+                level.myStock,
+                h + level.height() );
         }
 
         AllocateOrder(
@@ -309,7 +331,7 @@ bool CS2Pack2(
     if( ! packedCount )
     {
         std::cout << "nothing fit\n";
-        return false;
+        return;
     }
 
     // at least one order was cut for this stock
@@ -352,8 +374,6 @@ bool CS2Pack2(
         // add it to the instance cut list
         I.myCut.push_back( cut );
     }
-
-    return ( packedCount == level.size() );
 }
 
 void AllocateOrder(
@@ -376,13 +396,13 @@ void AllocateOrder(
 }
 void CutLevel(
     cInstance& I,
-    cLevel& level )
+    timber_t stock,
+    int h )
 {
-    timber_t stock = level.myStock;
 
-    stock->level( level.height() );
+    stock->level( h );
 
-    if( level.height() == stock->myHeight )
+    if( h == stock->myHeight )
     {
         //no need for a cut, we are at the top of the stock
         return;
@@ -390,8 +410,8 @@ void CutLevel(
     I.myCut.push_back( cCut(
                            stock,
                            'H',
-                           level.height(),
-                           level.height() ));
+                           h,
+                           h ));
 }
 
 void ReturnToInventory(
@@ -404,21 +424,12 @@ void ReturnToInventory(
             I.myStock.end(),
             [] ( timber_t t )
     {
-        std::cout << "remove? " <<t->isUsed() <<" " <<t->level() <<" "<<t->myHeight << "\n";
-        return( t->isUsed()  && t->level() == t->myHeight );
+        t->level( 0 );
+        t->used( false );
+        return( ! t->myHeight );
     } ),
     I.myStock.end() );
 
-    // adjust height of partially used stock
-    for( timber_t t : I.myStock )
-    {
-        if( ! t->isUsed() )
-            continue;
-
-        t->myHeight -= t->level();
-        t->level( 0 );
-        t->used( false );
-    }
 }
 void DisplayWastage( std::vector<cLevel>& levels )
 {
diff --git a/src/taInstance.cpp b/src/taInstance.cpp
index 7c70903..5172569 100644
--- a/src/taInstance.cpp
+++ b/src/taInstance.cpp
@@ -3,6 +3,7 @@
 #include <sstream>
 #include <memory>
 #include <vector>
+#include <set>
 #include <algorithm>
 #include "TimberAllocation.h"
 
@@ -38,6 +39,7 @@ void cInstance::read(
             break;
         }
     }
+    isEveryIDUnique();
     Inventory.expandCount();
     expandCount();
 }
@@ -95,5 +97,38 @@ void cInstance::addUnpacked( timberv_t& unpacked )
         myUnpacked.end(),
         unpacked.begin(), unpacked.end() );
 }
+bool cInstance::isEveryIDUnique()
+{
+    std::set<std::string> IDset, dupIDset;
+    bool first = true;
+    for( timber_t t: myOrder )
+    {
+        if( ! IDset.insert( t->myUserID ).second )
+        {
+            if( dupIDset.insert( t->myUserID ).second )
+            {
+                if( first )
+                {
+                    std::cout << "Discarding duplicate IDs ( tid11 ):\n";
+                    first = false;
+                }
+                std::cout << t->myUserID << " ";
+            }
+        }
+    }
+
+    myOrder.erase(
+        remove_if(
+            myOrder.begin(),
+            myOrder.end(),
+            [&dupIDset] ( timber_t t )
+    {
+        return( dupIDset.find(t->myUserID) != dupIDset.end() );
+    } ),
+    myOrder.end() );
+
+    std::cout <<  "\n" << myOrder.size() << " unique order IDs\n";
+    return true;
+}
 }
 
diff --git a/src/taLevel.cpp b/src/taLevel.cpp
index 2f8c2a3..0f84925 100644
--- a/src/taLevel.cpp
+++ b/src/taLevel.cpp
@@ -8,8 +8,12 @@
 
 namespace ta
 {
-void cLevel::removePacked()
+int cLevel::removePacked()
 {
+    int start = size();
+    if( ! start )
+        throw std::runtime_error( "removePacked");
+
     myOrder.erase(
         remove_if(
             myOrder.begin(),
@@ -19,7 +23,27 @@ void cLevel::removePacked()
         return( t->isPacked() );
     } ),
     myOrder.end() );
+
+    int stop = size();
+    int ret;
+    if( stop == start )
+        ret = 0;
+    else if( stop )
+        ret = 1;
+    else
+        ret = 2;
+
+    if( ret )
+        myStock->myHeight -= height();
+
+    return ret;
 }
+int cLevel::wastage() const
+    {
+        if( ! size() )
+            return 0;
+        return height() * ( myStock->myLength * myStock->myWidth - myAreaUsed );
+    }
 std::string cLevel::text() const
 {
     std::stringstream ss;
diff --git a/src/taTimber.cpp b/src/taTimber.cpp
index fa220bb..523c622 100644
--- a/src/taTimber.cpp
+++ b/src/taTimber.cpp
@@ -49,6 +49,7 @@ void cTimber::pack( int l, int w, int h, timber_t stock )
     myLocW = w;
     myLocH = h;
     myStock = stock;
+    stock->used();
 }