diff --git a/ClosedXML/ClosedXML/ClosedXML/Excel/PageSetup/IXLPageSetup.cs b/ClosedXML/ClosedXML/ClosedXML/Excel/PageSetup/IXLPageSetup.cs
index e588bdb..b688db5 100644
--- a/ClosedXML/ClosedXML/ClosedXML/Excel/PageSetup/IXLPageSetup.cs
+++ b/ClosedXML/ClosedXML/ClosedXML/Excel/PageSetup/IXLPageSetup.cs
@@ -158,7 +158,7 @@
         /// Gets or sets the page number that will begin the printout.
         /// <para>For example, the first page of your printout could be numbered page 5.</para>
         /// </summary>
-        Int32 FirstPageNumber { get; set; }
+        UInt32 FirstPageNumber { get; set; }
         /// <summary>
         /// Gets or sets a value indicating whether the worksheet will be centered on the page horizontally.
         /// </summary>
@@ -288,7 +288,7 @@
         IXLPageSetup SetScale(Int32 value);
         IXLPageSetup SetHorizontalDpi(Int32 value);
         IXLPageSetup SetVerticalDpi(Int32 value);
-        IXLPageSetup SetFirstPageNumber(Int32 value);
+        IXLPageSetup SetFirstPageNumber(UInt32 value);
         IXLPageSetup SetCenterHorizontally(); IXLPageSetup SetCenterHorizontally(Boolean value);
         IXLPageSetup SetCenterVertically(); IXLPageSetup SetCenterVertically(Boolean value);
         IXLPageSetup SetPaperSize(XLPaperSize value);
diff --git a/ClosedXML/ClosedXML/ClosedXML/Excel/PageSetup/XLPageSetup.cs b/ClosedXML/ClosedXML/ClosedXML/Excel/PageSetup/XLPageSetup.cs
index 14d2724..10273a9 100644
--- a/ClosedXML/ClosedXML/ClosedXML/Excel/PageSetup/XLPageSetup.cs
+++ b/ClosedXML/ClosedXML/ClosedXML/Excel/PageSetup/XLPageSetup.cs
@@ -106,7 +106,7 @@
         public XLPaperSize PaperSize { get; set; }
         public Int32 HorizontalDpi { get; set; }
         public Int32 VerticalDpi { get; set; }
-        public Int32 FirstPageNumber { get; set; }
+        public UInt32 FirstPageNumber { get; set; }
         public Boolean CenterHorizontally { get; set; }
         public Boolean CenterVertically { get; set; }
         public XLPrintErrorValues PrintErrorValue { get; set; }
@@ -217,7 +217,7 @@
         public IXLPageSetup SetScale(Int32 value) { Scale = value; return this; }
         public IXLPageSetup SetHorizontalDpi(Int32 value) { HorizontalDpi = value; return this; }
         public IXLPageSetup SetVerticalDpi(Int32 value) { VerticalDpi = value; return this; }
-        public IXLPageSetup SetFirstPageNumber(Int32 value) { FirstPageNumber = value; return this; }
+        public IXLPageSetup SetFirstPageNumber(UInt32 value) { FirstPageNumber = value; return this; }
         public IXLPageSetup SetCenterHorizontally() { CenterHorizontally = true; return this; }	public IXLPageSetup SetCenterHorizontally(Boolean value) { CenterHorizontally = value; return this; }
         public IXLPageSetup SetCenterVertically() { CenterVertically = true; return this; }	public IXLPageSetup SetCenterVertically(Boolean value) { CenterVertically = value; return this; }
         public IXLPageSetup SetPaperSize(XLPaperSize value) { PaperSize = value; return this; }
diff --git a/ClosedXML/ClosedXML/ClosedXML/Excel/XLWorkbook_Load.cs b/ClosedXML/ClosedXML/ClosedXML/Excel/XLWorkbook_Load.cs
index ab65137..54d233e 100644
--- a/ClosedXML/ClosedXML/ClosedXML/Excel/XLWorkbook_Load.cs
+++ b/ClosedXML/ClosedXML/ClosedXML/Excel/XLWorkbook_Load.cs
@@ -1573,7 +1573,7 @@
             if (pageSetup.HorizontalDpi != null) ws.PageSetup.HorizontalDpi = (Int32) pageSetup.HorizontalDpi.Value;
             if (pageSetup.VerticalDpi != null) ws.PageSetup.VerticalDpi = (Int32) pageSetup.VerticalDpi.Value;
             if (pageSetup.FirstPageNumber != null)
-                ws.PageSetup.FirstPageNumber = Int32.Parse(pageSetup.FirstPageNumber.InnerText);
+                ws.PageSetup.FirstPageNumber = UInt32.Parse(pageSetup.FirstPageNumber.InnerText);
         }
 
         private static void LoadPageMargins(PageMargins pageMargins, XLWorksheet ws)
diff --git a/ClosedXML/ClosedXML/ClosedXML_Sandbox/Program.cs b/ClosedXML/ClosedXML/ClosedXML_Sandbox/Program.cs
index 72feca3..5231600 100644
--- a/ClosedXML/ClosedXML/ClosedXML_Sandbox/Program.cs
+++ b/ClosedXML/ClosedXML/ClosedXML_Sandbox/Program.cs
@@ -12,15 +12,8 @@
     {
         static void Main(string[] args)
         {
-            var wb = new XLWorkbook();
-            var ws = wb.AddWorksheet("Sheet1");
-
-            ws.Range("A2:A3").Merge();
-            Console.WriteLine(ws.Range("A1:A2").IsMerged());
-            Console.WriteLine(ws.Range("A2:A3").IsMerged());
-            Console.WriteLine(ws.Range("A1:A4").IsMerged());
-            Console.WriteLine(ws.Range("A4:A5").IsMerged());
-
+            var wb = new XLWorkbook(@"c:\temp\issue.xlsx");
+            wb.SaveAs(@"c:\temp\issue_saved.xlsx");
             Console.WriteLine("Done");
             Console.ReadKey();
         }