diff --git a/ROMVault2/FileScanning.cs b/ROMVault2/FileScanning.cs
index e8b3726..698c1c4 100644
--- a/ROMVault2/FileScanning.cs
+++ b/ROMVault2/FileScanning.cs
@@ -820,11 +820,12 @@ namespace ROMVault2
                     tFile.FileStatusSet(FileStatus.SHA1CHDVerified);
                     return;
                 case CHD.CHDManCheck.Corrupt:
-                    _bgw.ReportProgress(0, new bgwShowError(error, filename));
+                    _bgw.ReportProgress(0, new bgwShowError(filename, error));
                     tFile.GotStatus = GotStatus.Corrupt;
                     return;
+                case CHD.CHDManCheck.CHDReturnError:
                 case CHD.CHDManCheck.CHDUnknownError:
-                    _bgw.ReportProgress(0, new bgwShowError(error, filename));
+                    _bgw.ReportProgress(0, new bgwShowError(filename, error));
                     return;
                 case CHD.CHDManCheck.ChdmanNotFound:
                     return;
diff --git a/ROMVault2/SupportedFiles/CHD/CHD.cs b/ROMVault2/SupportedFiles/CHD/CHD.cs
index 36131b7..df116da 100644
--- a/ROMVault2/SupportedFiles/CHD/CHD.cs
+++ b/ROMVault2/SupportedFiles/CHD/CHD.cs
@@ -245,10 +245,14 @@ namespace ROMVault2.SupportedFiles.CHD
             _result = "";
             _resultType = CHDManCheck.Unset;
 
-            string chdPath = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "chdman.exe");
+            string chdExe = "chdman.exe";
+            if (Settings.MonoFileIO)
+                chdExe = "chdman";
+
+            string chdPath = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, chdExe);
             if (!File.Exists(chdPath))
             {
-                result = "chdman not found";
+                result = chdExe + " Not Found.";
                 return CHDManCheck.ChdmanNotFound;
             }
 
@@ -330,7 +334,7 @@ namespace ROMVault2.SupportedFiles.CHD
             switch (_outputLineCount)
             {
                 case 0:
-                    if (sOut.Length < 53 || sOut.Substring(0, 53) != "chdman - MAME Compressed Hunks of Data (CHD) manager ")
+                    if (!System.Text.RegularExpressions.Regex.IsMatch(sOut, @"^chdman - MAME Compressed Hunks of Data \(CHD\) manager ([0-9\.]+) \(.*\)")) 
                     {
                         _result = "Incorrect startup of CHDMan :" + sOut;
                         _resultType = CHDManCheck.CHDReturnError;
@@ -367,70 +371,61 @@ namespace ROMVault2.SupportedFiles.CHD
             // Collect the process command output.
             if (String.IsNullOrEmpty(outLine.Data)) return;
 
-            string sOut = outLine.Data;
-            ReportError.LogOut("CHDError: " + sOut);
+            // We can get fed multiple lines worth of data because of \r line feeds
+            string[] sLines = outLine.Data.Split(new string[] { "\r" }, StringSplitOptions.None);
 
-            _bgw.ReportProgress(0, new bgwText3(sOut));
+            foreach (string sLine in sLines) {
 
-            if (_resultType != CHDManCheck.Unset)
-            {
-                if(_errorLines>0)
+                if (string.IsNullOrEmpty(sLine)) continue;
+
+                ReportError.LogOut("CHDError: " + sLine);
+                _bgw.ReportProgress(0, new bgwText3(sLine));
+ 
+                if (_resultType != CHDManCheck.Unset)
                 {
-                    _errorLines -= 1;
-                    _result += "\r\n" + sOut;
+                    if (_errorLines>0)
+                    {
+                        _errorLines -= 1;
+                        _result += "\r\n" + sLine;
+                    }
+                }
+                else if (System.Text.RegularExpressions.Regex.IsMatch(sLine, @"^No verification to be done; CHD has (uncompressed|no checksum)"))
+                {
+                    _result = sLine;
+                    _resultType = CHDManCheck.Corrupt;
+                } 
+                else if (System.Text.RegularExpressions.Regex.IsMatch(sLine, @"^Error (opening|reading) CHD file.*")) 
+                {
+                     _result = sLine;
+                    _resultType = CHDManCheck.Corrupt;
+                }
+                else if (System.Text.RegularExpressions.Regex.IsMatch(sLine, @"^Error opening parent CHD file .*:")) 
+                {
+                    _result = sLine;
+                    _resultType = CHDManCheck.Corrupt;
+                }
+                else if (System.Text.RegularExpressions.Regex.IsMatch(sLine, @"^Error: (Raw|Overall) SHA1 in header"))
+                {
+                    _result = sLine;
+                    _resultType = CHDManCheck.Corrupt;
+                }
+                else if (System.Text.RegularExpressions.Regex.IsMatch(sLine, @"^Out of memory"))
+                {
+                    _result = sLine;
+                    _resultType = CHDManCheck.Corrupt;
+                }
+                // Verifying messages are a non-error
+                else if (System.Text.RegularExpressions.Regex.IsMatch(sLine, @"Verifying, \d+\.\d+\% complete\.\.\."))
+                {
+
+                }
+                else
+                {
+                    ReportError.SendErrorMessage("CHDErrorHandler returned =" + sLine);
+                    _result = "Unknown message : " + sLine;
+                    _resultType = CHDManCheck.CHDUnknownError;
                 }
-                return;
             }
-
-            if (sOut.Length > 44)
-                if (sOut.Substring(0, 23) == "Error reading CHD file " && sOut.Substring(sOut.Length - 21, 21) == ": decompression error")
-                {
-                    _result = sOut;
-                    _resultType = CHDManCheck.Corrupt;
-                    return;
-                }
-            if (sOut.Length > 35)
-                if (sOut.Substring(0, 23) == "Error opening CHD file " && sOut.Substring(sOut.Length - 21, 21) == ": decompression error")
-                {
-                    _result = sOut;
-                    _resultType = CHDManCheck.Corrupt;
-                    return;
-                }
-            if (sOut.Length > 35)
-                if (sOut.Substring(0, 23) == "Error opening CHD file " && sOut.Substring(sOut.Length - 12, 12) == ": read error")
-                {
-                    _result = sOut;
-                    _resultType = CHDManCheck.Corrupt;
-                    return;
-                }
-            if (sOut.Length > 25)
-                if (sOut.Substring(0, 25) == "Error: Raw SHA1 in header")
-                {
-                    _result = sOut;
-                    _errorLines = 1;
-                    _resultType = CHDManCheck.Corrupt;
-                    return;
-                }
-            if (sOut.Length == 13)
-                if (sOut == "Out of memory")
-                {
-                    _result = sOut;
-                    _resultType = CHDManCheck.Corrupt;
-                    return;
-                }
-
-            // check for Verifying message
-            if (sOut.Length >= 24)
-                if (sOut.Substring(0, 11) == "Verifying, " && sOut.Substring(sOut.Length - 13, 13) == " complete... ")
-                {
-                    //_resultType = CHDManCheck.Good;
-                    return;
-                }
-
-
-            ReportError.SendErrorMessage("CHDErrorHandler returned =" + sOut);
-            _result = "Unknown message : " + sOut;
-            _resultType = CHDManCheck.CHDUnknownError;
         }