diff --git a/src/Build.Shared.props b/src/Build.Shared.props
index 66f3140..90a6744 100644
--- a/src/Build.Shared.props
+++ b/src/Build.Shared.props
@@ -15,7 +15,7 @@
     <PackageVersion_CdsSdkProxy>4.7.6346-master</PackageVersion_CdsSdkProxy>
     <PackageVersion_Newtonsoft>13.0.1</PackageVersion_Newtonsoft>
     <PackageVersion_RestClientRuntime>2.3.20</PackageVersion_RestClientRuntime>
-    <PackageVersion_XrmSdk>9.0.2.42</PackageVersion_XrmSdk>
+    <PackageVersion_XrmSdk>9.0.2.45</PackageVersion_XrmSdk>
     <PackageVersion_Dep_OutlookXrmSdk>9.0.2.34</PackageVersion_Dep_OutlookXrmSdk>
     <PackageVersion_BatchedTelemetry>2.0.19</PackageVersion_BatchedTelemetry>
     <PackageVersion_DataverseClient>0.4.20</PackageVersion_DataverseClient>
diff --git a/src/GeneralTools/DataverseClient/Client/ConnectionService.cs b/src/GeneralTools/DataverseClient/Client/ConnectionService.cs
index 3a322ec..326eaa0 100644
--- a/src/GeneralTools/DataverseClient/Client/ConnectionService.cs
+++ b/src/GeneralTools/DataverseClient/Client/ConnectionService.cs
@@ -1742,7 +1742,7 @@ internal async Task<OrganizationResponse> Command_WebAPIProcess_ExecuteAsync(Org
         {
             cancellationToken.ThrowIfCancellationRequested();
 
-            if (!Utilities.IsRequestValidForTranslationToWebAPI(req , inLoginFlow)) // THIS WILL GET REMOVED AT SOME POINT, TEMP FOR TRANSTION  //TODO:REMOVE ON COMPELTE
+            if (!Utilities.IsRequestValidForTranslationToWebAPI(req , inLoginFlow))
             {
                 logEntry.Log("Execute Organization Request failed, WebAPI is only supported for limited type of messages at this time.", TraceEventType.Error);
                 return null;
@@ -1750,15 +1750,16 @@ internal async Task<OrganizationResponse> Command_WebAPIProcess_ExecuteAsync(Org
 
             HttpMethod methodToExecute = Utilities.RequestNameToHttpVerb(req.RequestName);
             Entity cReq = null;
-            if (req.Parameters.ContainsKey("Target") && req.Parameters["Target"] is Entity ent) // this should cover things that have targets.
+            if (req.Parameters.ContainsKey("Target") && req.Parameters["Target"] is Entity ent) 
             {
                 cReq = ent;
             }
-            else if (req.Parameters.ContainsKey("Target") && req.Parameters["Target"] is EntityReference entRef) // this should cover things that have targets.
+            else if (req.Parameters.ContainsKey("Target") && req.Parameters["Target"] is EntityReference entRef)
             {
                 cReq = entRef.KeyAttributes.Any()
                     ? new Entity(entRef.LogicalName, entRef.KeyAttributes)
                     : new Entity(entRef.LogicalName, entRef.Id);
+                cReq.RowVersion = entRef.RowVersion; 
             }
 
             EntityMetadata entityMetadata = null;
@@ -1861,7 +1862,7 @@ internal async Task<OrganizationResponse> Command_WebAPIProcess_ExecuteAsync(Org
                 }
                 else
                 {
-                    DataverseOperationException opEx = new DataverseOperationException("Request Failed, RowVersion is missing and is required when ConcurrencyBehavior is set to a value other then Default.");
+                    DataverseOperationException opEx = new DataverseOperationException("Request Failed, RowVersion is missing and is required when ConcurrencyBehavior is set to a value other than Default.");
                     logEntry.Log(opEx);
                     return null;
                 }
@@ -2145,9 +2146,16 @@ internal async Task<HttpResponseMessage> Command_WebExecuteAsync(string queryStr
                         foreach (var hrdProp in addedHeaders)
                         {
                             // General handling from here on out.
-                            if (!customHeaders.ContainsKey(hrdProp.Key))
+                            if (customHeaders.Keys.Contains(hrdProp.Key))
                             {
-                                customHeaders[hrdProp.Key] = new List<string>() { hrdProp.Value };
+                                if (customHeaders[hrdProp.Key] == null)
+                                    customHeaders[hrdProp.Key] = new List<string>();
+
+                                customHeaders[hrdProp.Key].Add(hrdProp.Value);
+                            }
+                            else
+                            {
+                                customHeaders.Add(hrdProp.Key, new List<string>() { hrdProp.Value });
                             }
                         }
                         addedHeaders.Clear();
@@ -2359,30 +2367,24 @@ private bool ShouldRetryWebAPI(Exception ex, int retryCount, int maxRetryCount,
                     _httpRequest.RequestUri = new System.Uri(uri);
 
                     // Set Headers
+                    // Add User Agent and request id to send.
+                    string Agent = "Unknown";
+                    if (AppDomain.CurrentDomain != null)
+                    {
+                        Agent = AppDomain.CurrentDomain.FriendlyName;
+                    }
+                    Agent = $"{Agent} (DataverseSvcClient:{Environs.DvSvcClientFileVersion})";
+
+                    if (!_httpRequest.Headers.Contains(Utilities.RequestHeaders.USER_AGENT_HTTP_HEADER))
+                        _httpRequest.Headers.TryAddWithoutValidation(Utilities.RequestHeaders.USER_AGENT_HTTP_HEADER, string.IsNullOrEmpty(Agent) ? "" : Agent);
+
                     if (customHeaders != null)
                     {
                         foreach (var _header in customHeaders)
                         {
-                            if (_httpRequest.Headers.Count() > 0)
-                                if (_httpRequest.Headers.Contains(_header.Key))
-                                {
-                                    _httpRequest.Headers.Remove(_header.Key);
-                                }
                             _httpRequest.Headers.TryAddWithoutValidation(_header.Key, _header.Value);
                         }
 
-                        // Add User Agent and request id to send.
-                        string Agent = "Unknown";
-                        if (AppDomain.CurrentDomain != null)
-                        {
-                            Agent = AppDomain.CurrentDomain.FriendlyName;
-                        }
-                        Agent = $"{Agent} (DataverseSvcClient:{Environs.DvSvcClientFileVersion})";
-
-
-                        if (!_httpRequest.Headers.Contains(Utilities.RequestHeaders.USER_AGENT_HTTP_HEADER))
-                            _httpRequest.Headers.TryAddWithoutValidation(Utilities.RequestHeaders.USER_AGENT_HTTP_HEADER, string.IsNullOrEmpty(Agent) ? "" : Agent);
-
                         if (!_httpRequest.Headers.Contains(Utilities.RequestHeaders.X_MS_CLIENT_REQUEST_ID))
                             _httpRequest.Headers.TryAddWithoutValidation(Utilities.RequestHeaders.X_MS_CLIENT_REQUEST_ID, RequestId.ToString());
 
diff --git a/src/GeneralTools/DataverseClient/Client/DataverseTelemetryBehaviors.cs b/src/GeneralTools/DataverseClient/Client/DataverseTelemetryBehaviors.cs
index f5e55ad..c430dfd 100644
--- a/src/GeneralTools/DataverseClient/Client/DataverseTelemetryBehaviors.cs
+++ b/src/GeneralTools/DataverseClient/Client/DataverseTelemetryBehaviors.cs
@@ -279,6 +279,7 @@ public object BeforeSendRequest(ref Message request, IClientChannel channel)
                 }
 
                 AddExternalHeaders(httpRequestMessage);
+                Utilities.CleanUpHeaderKeys(httpRequestMessage.Headers); 
                 if (httpRequestMessageObject == null)
                     request.Properties.Add(HttpRequestMessageProperty.Name, httpRequestMessage);
             }
diff --git a/src/GeneralTools/DataverseClient/Client/ServiceClient.cs b/src/GeneralTools/DataverseClient/Client/ServiceClient.cs
index f4fccfb..1cbb5a4 100644
--- a/src/GeneralTools/DataverseClient/Client/ServiceClient.cs
+++ b/src/GeneralTools/DataverseClient/Client/ServiceClient.cs
@@ -391,6 +391,7 @@ internal WhoAmIResponse SystemUser
                     else
                     {
                         WhoAmIResponse resp = Task.Run(async () => await _connectionSvc.GetWhoAmIDetails(this).ConfigureAwait(false)).Result;
+                        //WhoAmIResponse resp = _connectionSvc.GetWhoAmIDetails(this).Result;
                         _connectionSvc.CurrentUser = resp;
                         return resp;
                     }
diff --git a/src/GeneralTools/DataverseClient/Client/Utils/Utils.cs b/src/GeneralTools/DataverseClient/Client/Utils/Utils.cs
index 06ac16a..9291b92 100644
--- a/src/GeneralTools/DataverseClient/Client/Utils/Utils.cs
+++ b/src/GeneralTools/DataverseClient/Client/Utils/Utils.cs
@@ -562,7 +562,10 @@ internal static ExpandoObject ToExpandoObject(Entity sourceEntity, MetadataUtili
                             {
                                 mselectValueString += $"{opt.Value},";
                             }
-                            value = mselectValueString.Remove(mselectValueString.Length - 1);
+                            if (!string.IsNullOrEmpty(mselectValueString) && mselectValueString.Last().Equals(','))
+                                value = mselectValueString.Remove(mselectValueString.Length - 1);
+                            else
+                                value = null;
                         }
                         else if (value is OptionSetValue optionSetValue)
                         {
@@ -1212,5 +1215,24 @@ private static Dictionary<string, string> ConvertCookieArraysToCookieDictionary(
         }
         #endregion
 
+        #region HTTPHeaderCleanupSupport
+        /// <summary>
+        /// Fix for issue in .net core which is not using proper separators for User-Agent and Server Headers
+        /// </summary>
+        /// <param name="headerCollection">Collection to clean up values for</param>
+        /// <returns></returns>
+        internal static void CleanUpHeaderKeys(WebHeaderCollection headerCollection)
+        {
+            if (headerCollection.AllKeys.Contains(RequestHeaders.USER_AGENT_HTTP_HEADER))
+            {
+                string UserAgentValue = headerCollection[RequestHeaders.USER_AGENT_HTTP_HEADER];
+                if (UserAgentValue.Contains(","))
+                {
+                    headerCollection[RequestHeaders.USER_AGENT_HTTP_HEADER] = UserAgentValue.Replace(",", " ");
+                }
+            }
+        }
+        #endregion
+
     }
 }
diff --git a/src/nuspecs/Microsoft.PowerPlatform.Dataverse.Client.ReleaseNotes.txt b/src/nuspecs/Microsoft.PowerPlatform.Dataverse.Client.ReleaseNotes.txt
index a2750dd..f25ae0b 100644
--- a/src/nuspecs/Microsoft.PowerPlatform.Dataverse.Client.ReleaseNotes.txt
+++ b/src/nuspecs/Microsoft.PowerPlatform.Dataverse.Client.ReleaseNotes.txt
@@ -7,6 +7,11 @@ Notice:
     Note: Only AD on FullFramework, OAuth, Certificate, ClientSecret Authentication types are supported at this time.
 
 ++CURRENTRELEASEID++
+Fixed an issue with Custom User Agent headers incorrectly causing a format error when .net core is used. Proper User-Agent format must be used to send requests including the user agent. 
+Fixed an issue with an Empty OptionSetValue collection causing an ArgumentOutOfRangeException. Empty OptionSetValue collections will now be mapped to Null. Fixes https://github.com/microsoft/PowerPlatform-DataverseServiceClient/issues/292 Thanks for your report! 
+Fixed an issue where EntityReference based operations do not propagate RowVersion when using WebAPI protocol.  Fixes https://github.com/microsoft/PowerPlatform-DataverseServiceClient/issues/296 
+
+1.0.4: 
 Fixed an issue with External Authentication and Connection and configuration constructor where external auth was not being respected correctly.
 Fixed a bug on clone where Ilogger was not being propagated to the cloned connection correctly
 Removed a call to WhoAmI during login flow as process of talking to Dataverse to verify the connection is delt with during get environment information call.