diff --git a/ClosedXML/ClosedXML/ClosedXML/Excel/Rows/XLRow.cs b/ClosedXML/ClosedXML/ClosedXML/Excel/Rows/XLRow.cs
index 07fd967..27f62c8 100644
--- a/ClosedXML/ClosedXML/ClosedXML/Excel/Rows/XLRow.cs
+++ b/ClosedXML/ClosedXML/ClosedXML/Excel/Rows/XLRow.cs
@@ -104,11 +104,28 @@
 
         #region IXLRow Members
 
+        private Boolean _loading;
+        public Boolean Loading
+        {
+            get { return IsReference ? Worksheet.Internals.RowsCollection[RowNumber()].Loading : _loading; }
+            set
+            {
+                if (IsReference)
+                    Worksheet.Internals.RowsCollection[RowNumber()].Loading = value;
+                else
+                    _loading = value;
+            }
+        }
+
+        public Boolean HeightChanged { get; private set; }
         public Double Height
         {
             get { return IsReference ? Worksheet.Internals.RowsCollection[RowNumber()].Height : _height; }
             set
             {
+                if (!Loading)
+                    HeightChanged = true;
+
                 if (IsReference)
                     Worksheet.Internals.RowsCollection[RowNumber()].Height = value;
                 else
@@ -680,5 +697,7 @@
 
             return base.IsEmpty(includeFormats);
         }
+
+        
     }
 }
\ No newline at end of file
diff --git a/ClosedXML/ClosedXML/ClosedXML/Excel/XLWorkbook_Load.cs b/ClosedXML/ClosedXML/ClosedXML/Excel/XLWorkbook_Load.cs
index 9445601..1e28ac2 100644
--- a/ClosedXML/ClosedXML/ClosedXML/Excel/XLWorkbook_Load.cs
+++ b/ClosedXML/ClosedXML/ClosedXML/Excel/XLWorkbook_Load.cs
@@ -889,10 +889,15 @@
                               Row row)
         {
             var xlRow = ws.Row((Int32) row.RowIndex.Value, false);
+            
             if (row.Height != null)
                 xlRow.Height = row.Height;
             else
+            {
+                xlRow.Loading = true;
                 xlRow.Height = ws.RowHeight;
+                xlRow.Loading = false;
+            }
 
             if (row.Hidden != null && row.Hidden)
                 xlRow.Hide();
diff --git a/ClosedXML/ClosedXML/ClosedXML/Excel/XLWorkbook_Save.cs b/ClosedXML/ClosedXML/ClosedXML/Excel/XLWorkbook_Save.cs
index 7aa6233..ab429b9 100644
--- a/ClosedXML/ClosedXML/ClosedXML/Excel/XLWorkbook_Save.cs
+++ b/ClosedXML/ClosedXML/ClosedXML/Excel/XLWorkbook_Save.cs
@@ -2819,18 +2819,19 @@
                 if (xlWorksheet.Internals.RowsCollection.ContainsKey(distinctRow))
                 {
                     var thisRow = xlWorksheet.Internals.RowsCollection[distinctRow];
-                    if (thisRow.Height != xlWorksheet.RowHeight)
+                    if (thisRow.HeightChanged)
                     {
                         row.Height = thisRow.Height;
                         row.CustomHeight = true;
+                        row.CustomFormat = true;
                     }
 
-                    //if (!thisRow.Style.Equals(xlWorksheet.Style))
                     if (thisRow.GetStyleId() != xlWorksheet.GetStyleId())
                     {
                         row.StyleIndex = context.SharedStyles[thisRow.GetStyleId()].StyleId;
                         row.CustomFormat = true;
                     }
+
                     if (thisRow.IsHidden)
                         row.Hidden = true;
                     if (thisRow.Collapsed)
diff --git a/ClosedXML/ClosedXML/ClosedXML/Excel/XLWorksheet.cs b/ClosedXML/ClosedXML/ClosedXML/Excel/XLWorksheet.cs
index 40f41db..bed215c 100644
--- a/ClosedXML/ClosedXML/ClosedXML/Excel/XLWorksheet.cs
+++ b/ClosedXML/ClosedXML/ClosedXML/Excel/XLWorksheet.cs
@@ -867,17 +867,16 @@
         public IXLRows RowsUsed(Boolean includeFormats = false, Func<IXLRow, Boolean> predicate = null)
         {
             var rows = new XLRows(Worksheet);
-            using (var asRange = AsRange())
+            var rowsUsed = new HashSet<Int32>();
+            Internals.RowsCollection.Keys.ForEach(r => rowsUsed.Add(r));
+            Internals.CellsCollection.RowsUsed.Keys.ForEach(r => rowsUsed.Add(r));
+            foreach (var rowNum in rowsUsed)
             {
-                var rowsUsed = asRange.RowsUsed(includeFormats);
-                foreach (IXLRangeRow row in rowsUsed)
-                {
-                    var retRow = Row(row.RowNumber());
-                    if (predicate == null || predicate(retRow))
-                        rows.Add(retRow);
-                    else 
-                        retRow.Dispose();
-                }
+                var row = Row(rowNum);
+                if (!row.IsEmpty(includeFormats) && (predicate == null || predicate(row)))
+                    rows.Add(row);
+                else
+                    row.Dispose();
             }
             return rows;
         }
@@ -889,17 +888,16 @@
         public IXLColumns ColumnsUsed(Boolean includeFormats = false, Func<IXLColumn, Boolean> predicate = null)
         {
             var columns = new XLColumns(Worksheet);
-            using (var asRange = AsRange())
+            var columnsUsed = new HashSet<Int32>();
+            Internals.ColumnsCollection.Keys.ForEach(r => columnsUsed.Add(r));
+            Internals.CellsCollection.ColumnsUsed.Keys.ForEach(r => columnsUsed.Add(r));
+            foreach (var columnNum in columnsUsed)
             {
-                var columnsUsed = asRange.ColumnsUsed(includeFormats);
-                foreach (IXLRangeColumn column in columnsUsed)
-                {
-                    var retColumn = Column(column.ColumnNumber());
-                    if (predicate == null || predicate(retColumn))
-                        columns.Add(retColumn);
-                    else
-                        retColumn.Dispose();
-                }
+                var column = Column(columnNum);
+                if (!column.IsEmpty(includeFormats) && (predicate == null || predicate(column)))
+                    columns.Add(column);
+                else
+                    column.Dispose();
             }
             return columns;
         }
diff --git a/ClosedXML/ClosedXML/ClosedXML/Properties/AssemblyInfo.cs b/ClosedXML/ClosedXML/ClosedXML/Properties/AssemblyInfo.cs
index 214b1d9..0e076ac 100644
--- a/ClosedXML/ClosedXML/ClosedXML/Properties/AssemblyInfo.cs
+++ b/ClosedXML/ClosedXML/ClosedXML/Properties/AssemblyInfo.cs
@@ -31,6 +31,6 @@
 // You can specify all the values or you can default the Build and Revision Numbers 
 // by using the '*' as shown below:
 // [assembly: AssemblyVersion("1.0.*")]
-[assembly: AssemblyVersion("0.63.0.0")]
-[assembly: AssemblyFileVersion("0.63.0.0")]
+[assembly: AssemblyVersion("0.64.0.0")]
+[assembly: AssemblyFileVersion("0.64.0.0")]
 [assembly: System.Runtime.CompilerServices.InternalsVisibleTo("ClosedXML_Tests, PublicKey=0024000004800000940000000602000000240000525341310004000001000100a1fb8ba59167fe734d64128ca73d32c45cb8a117246d09c95c8769db88fe332b0a3396bedd0ea48ee42b0e5796fec0798ca5cb628a9a6de80d35d6c67b936ca1670347b3d4f2b769c8ce2ddcf959dbac6bcd88e6c08751ea1fffa0522de3507193e7035305a8aa008d6c88cca1341b3120fa9c347ab3f97e2d772e2709277da5")]
\ No newline at end of file
diff --git a/ClosedXML/ClosedXML/ClosedXML_Net3.5/Properties/AssemblyInfo.cs b/ClosedXML/ClosedXML/ClosedXML_Net3.5/Properties/AssemblyInfo.cs
index 8ed1a8b..0e1d43f 100644
--- a/ClosedXML/ClosedXML/ClosedXML_Net3.5/Properties/AssemblyInfo.cs
+++ b/ClosedXML/ClosedXML/ClosedXML_Net3.5/Properties/AssemblyInfo.cs
@@ -31,5 +31,5 @@
 // You can specify all the values or you can default the Build and Revision Numbers 
 // by using the '*' as shown below:
 // [assembly: AssemblyVersion("1.0.*")]
-[assembly: AssemblyVersion("0.63.0.0")]
-[assembly: AssemblyFileVersion("0.63.0.0")]
+[assembly: AssemblyVersion("0.64.0.0")]
+[assembly: AssemblyFileVersion("0.64.0.0")]
diff --git a/ClosedXML/ClosedXML/ClosedXML_Tests/Resource/Examples/Misc/AdjustToContents.xlsx b/ClosedXML/ClosedXML/ClosedXML_Tests/Resource/Examples/Misc/AdjustToContents.xlsx
index 152d37a..30b3eb6 100644
--- a/ClosedXML/ClosedXML/ClosedXML_Tests/Resource/Examples/Misc/AdjustToContents.xlsx
+++ b/ClosedXML/ClosedXML/ClosedXML_Tests/Resource/Examples/Misc/AdjustToContents.xlsx
Binary files differ
diff --git a/ClosedXML/ClosedXML/ClosedXML_Tests/Resource/Examples/Rows/RowCollection.xlsx b/ClosedXML/ClosedXML/ClosedXML_Tests/Resource/Examples/Rows/RowCollection.xlsx
index c37d8bc..63bd02d 100644
--- a/ClosedXML/ClosedXML/ClosedXML_Tests/Resource/Examples/Rows/RowCollection.xlsx
+++ b/ClosedXML/ClosedXML/ClosedXML_Tests/Resource/Examples/Rows/RowCollection.xlsx
Binary files differ