diff --git a/.travis.yml b/.travis.yml
index 8e4ca07..a39183a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -11,7 +11,7 @@ addons:
     - libunwind8
     - zlib1g
 before_install:
-  - if test "$TRAVIS_OS_NAME" == "osx"; then brew update; brew install icu4c; brew install openssl; brew link --force openssl; fi
+  - if test "$TRAVIS_OS_NAME" == "osx"; then brew update; brew install openssl; brew link --force openssl; fi
 mono:
   - 4.0.5
 os:
@@ -19,6 +19,4 @@ os:
   - osx
 osx_image: xcode7.1
 script:
-  - ./build.sh --quiet verify
-env:
-  - KOREBUILD_TEST_SKIPMONO=1
\ No newline at end of file
+  - ./build.sh --quiet verify
\ No newline at end of file
diff --git a/build.ps1 b/build.ps1
index 8f2f996..6d49c4d 100644
--- a/build.ps1
+++ b/build.ps1
@@ -33,7 +33,7 @@ cd $PSScriptRoot
 $repoFolder = $PSScriptRoot
 $env:REPO_FOLDER = $repoFolder
 
-$koreBuildZip="https://github.com/aspnet/KoreBuild/archive/dev.zip"
+$koreBuildZip="https://github.com/aspnet/KoreBuild/archive/1.0.0.zip"
 if ($env:KOREBUILD_ZIP)
 {
     $koreBuildZip=$env:KOREBUILD_ZIP
diff --git a/build.sh b/build.sh
index f420810..a55d3eb 100755
--- a/build.sh
+++ b/build.sh
@@ -2,7 +2,7 @@
 repoFolder="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
 cd $repoFolder
 
-koreBuildZip="https://github.com/aspnet/KoreBuild/archive/dev.zip"
+koreBuildZip="https://github.com/aspnet/KoreBuild/archive/1.0.0.zip"
 if [ ! -z $KOREBUILD_ZIP ]; then
     koreBuildZip=$KOREBUILD_ZIP
 fi
diff --git a/src/Dapper.FluentMap.Dommel/project.json b/src/Dapper.FluentMap.Dommel/project.json
index 880cd24..a6ba0f6 100644
--- a/src/Dapper.FluentMap.Dommel/project.json
+++ b/src/Dapper.FluentMap.Dommel/project.json
@@ -1,5 +1,5 @@
 {
-  "version": "1.4.0",
+  "version": "1.4.1",
   "description": "Dapper.FluentMap extension for Dommel support.",
   "authors": [ "Henk Mollema" ],
   "copyright": "Copyright © Henk Mollema 2016",
@@ -11,8 +11,8 @@
   },
 
   "dependencies": {
-    "Dapper.FluentMap": "1.5.0",
-    "Dommel": "1.6.0"
+    "Dapper.FluentMap": "1.5.1",
+    "Dommel": "1.6.1"
   },
 
   "frameworks": {
diff --git a/src/Dapper.FluentMap/Configuration/FluentMapConfiguration.cs b/src/Dapper.FluentMap/Configuration/FluentMapConfiguration.cs
index 16e6f42..024238a 100644
--- a/src/Dapper.FluentMap/Configuration/FluentMapConfiguration.cs
+++ b/src/Dapper.FluentMap/Configuration/FluentMapConfiguration.cs
@@ -1,4 +1,5 @@
 using System;
+using System.Linq;
 using System.ComponentModel;
 using Dapper.FluentMap.Conventions;
 using Dapper.FluentMap.Mapping;
@@ -24,6 +25,10 @@ public void AddMap<TEntity>(IEntityMap<TEntity> mapper) where TEntity : class
             {
                 FluentMapper.AddTypeMap<TEntity>();
             }
+            else
+            {
+                throw new InvalidOperationException($"Adding entity map for type '{typeof(TEntity)}' failed. The type already exists. Current entity maps: " + string.Join(", ", FluentMapper.EntityMaps.Select(e => e.Key.ToString())));
+            }
         }
 
         /// <summary>
diff --git a/src/Dapper.FluentMap/project.json b/src/Dapper.FluentMap/project.json
index 13b6997..db81b9f 100644
--- a/src/Dapper.FluentMap/project.json
+++ b/src/Dapper.FluentMap/project.json
@@ -1,5 +1,5 @@
 {
-  "version": "1.5.0",
+  "version": "1.5.1",
   "description": "Simple API to fluently map POCO properties to database columns when using Dapper.",
   "authors": [ "Henk Mollema" ],
   "copyright": "Copyright © Henk Mollema 2016",
@@ -11,7 +11,7 @@
   },
 
   "dependencies": {
-    "Dapper": "1.50.0-rc2b"
+    "Dapper": "1.50.0"
   },
 
   "frameworks": {
@@ -32,8 +32,7 @@
         "define": [ "COREFX" ]
       },
       "dependencies": {
-        "NETStandard.Library": "1.5.0-rc2-24027",
-        "System.Reflection.TypeExtensions": "4.1.0-rc2-24027"
+        "NETStandard.Library": "1.6.0"
       }
     }
   },
diff --git a/test/Dapper.FluentMap.Tests/project.json b/test/Dapper.FluentMap.Tests/project.json
index 954e64c..7771179 100644
--- a/test/Dapper.FluentMap.Tests/project.json
+++ b/test/Dapper.FluentMap.Tests/project.json
@@ -1,26 +1,22 @@
 {
   "dependencies": {
-    "Dapper.FluentMap": "1.5.0",
-    "xunit": "2.1.0",
-    "dotnet-test-xunit": "1.0.0-rc2-build10015",
-    "Microsoft.NETCore.Platforms": "1.0.1-rc2-24027"
+    "Dapper.FluentMap": "1.5.1",
+    "dotnet-test-xunit": "2.2.0-*",
+    "xunit": "2.2.0-*"
   },
 
   "frameworks": {
+    "net451": {},
     "netcoreapp1.0": {
       "buildOptions": {
         "define": [ "COREFX" ]
       },
       "dependencies": {
         "Microsoft.NETCore.App": {
-          "version": "1.0.0-rc2-3002702",
+          "version": "1.0.0",
           "type": "platform"
         }
-      },
-      "imports": [
-        "dnxcore50",
-        "portable-net451+win8"
-      ]
+      }
     }
   },