diff --git a/source/RobotAPI/components/skills/SkillProviderExample/aron/HelloWorldAcceptedType.xml b/source/RobotAPI/components/skills/SkillProviderExample/aron/HelloWorldAcceptedType.xml
index 10c81ab542736b5a06bcd605f95353a619c3ad25..7e77eacbea7ecd5aa234fa90bb3df1df56e70557 100644
--- a/source/RobotAPI/components/skills/SkillProviderExample/aron/HelloWorldAcceptedType.xml
+++ b/source/RobotAPI/components/skills/SkillProviderExample/aron/HelloWorldAcceptedType.xml
@@ -16,6 +16,12 @@
             <ObjectChild key='some_int'>
                 <int32 />
             </ObjectChild>
+            <ObjectChild key='some_int_enum'>
+                <HelloWorldInteEnum />
+            </ObjectChild>
+            <ObjectChild key='some_optional_int_enum'>
+                <HelloWorldInteEnum optional="true" />
+            </ObjectChild>
             <ObjectChild key='some_float'>
                 <float32 />
             </ObjectChild>
diff --git a/source/RobotAPI/libraries/skills_gui/aron_tree_widget/visitors/AronTreeWidgetConverter.cpp b/source/RobotAPI/libraries/skills_gui/aron_tree_widget/visitors/AronTreeWidgetConverter.cpp
index 832258ea2c1083742ae9c0f13192e9f6903169ef..23be73d02da766a0b361f53cb53486fd91d65684 100644
--- a/source/RobotAPI/libraries/skills_gui/aron_tree_widget/visitors/AronTreeWidgetConverter.cpp
+++ b/source/RobotAPI/libraries/skills_gui/aron_tree_widget/visitors/AronTreeWidgetConverter.cpp
@@ -93,7 +93,7 @@ namespace armarx::skills::gui
         if (i->getMaybe() != armarx::aron::type::Maybe::NONE)
         {
             // its a maybetype. We have to check the state
-            if (el->checkState(1) == Qt::CheckState::Unchecked)
+            if (el->checkState(2) == Qt::CheckState::Unchecked)
             {
                 createdAron = nullptr;
                 return;
@@ -126,7 +126,7 @@ namespace armarx::skills::gui
         if (i->getMaybe() != armarx::aron::type::Maybe::NONE)
         {
             // its a maybetype. We have to check the state
-            if (el->checkState(1) == Qt::CheckState::Unchecked)
+            if (el->checkState(2) == Qt::CheckState::Unchecked)
             {
                 createdAron = nullptr;
                 return;
@@ -159,7 +159,7 @@ namespace armarx::skills::gui
         if (i->getMaybe() != armarx::aron::type::Maybe::NONE)
         {
             // its a maybetype. We have to check the state
-            if (el->checkState(1) == Qt::CheckState::Unchecked)
+            if (el->checkState(2) == Qt::CheckState::Unchecked)
             {
                 createdAron = nullptr;
                 return;
@@ -192,7 +192,7 @@ namespace armarx::skills::gui
         if (i->getMaybe() != armarx::aron::type::Maybe::NONE)
         {
             // its a maybetype. We have to check the state
-            if (el->checkState(1) == Qt::CheckState::Unchecked)
+            if (el->checkState(2) == Qt::CheckState::Unchecked)
             {
                 createdAron = nullptr;
                 return;
@@ -221,7 +221,7 @@ namespace armarx::skills::gui
         if (i->getMaybe() != armarx::aron::type::Maybe::NONE)
         {
             // its a maybetype. We have to check the state
-            if (el->checkState(1) == Qt::CheckState::Unchecked)
+            if (el->checkState(2) == Qt::CheckState::Unchecked)
             {
                 createdAron = nullptr;
                 return;
@@ -316,7 +316,7 @@ namespace armarx::skills::gui
         if (i->getMaybe() != armarx::aron::type::Maybe::NONE)
         {
             // its a maybetype. We have to check the state
-            if (el->checkState(1) == Qt::CheckState::Unchecked)
+            if (el->checkState(2) == Qt::CheckState::Unchecked)
             {
                 createdAron = nullptr;
                 return;
@@ -365,7 +365,7 @@ namespace armarx::skills::gui
         if (i->getMaybe() != armarx::aron::type::Maybe::NONE)
         {
             // its a maybetype. We have to check the state
-            if (el->checkState(1) == Qt::CheckState::Unchecked)
+            if (el->checkState(2) == Qt::CheckState::Unchecked)
             {
                 createdAron = nullptr;
                 return;
@@ -415,7 +415,7 @@ namespace armarx::skills::gui
         if (i->getMaybe() != armarx::aron::type::Maybe::NONE)
         {
             // its a maybetype. We have to check the state
-            if (el->checkState(1) == Qt::CheckState::Unchecked)
+            if (el->checkState(2) == Qt::CheckState::Unchecked)
             {
                 createdAron = nullptr;
                 return;
@@ -446,7 +446,7 @@ namespace armarx::skills::gui
         if (i->getMaybe() != armarx::aron::type::Maybe::NONE)
         {
             // its a maybetype. We have to check the state
-            if (el->checkState(1) == Qt::CheckState::Unchecked)
+            if (el->checkState(2) == Qt::CheckState::Unchecked)
             {
                 createdAron = nullptr;
                 return;
@@ -485,7 +485,7 @@ namespace armarx::skills::gui
         if (i->getMaybe() != armarx::aron::type::Maybe::NONE)
         {
             // its a maybetype. We have to check the state
-            if (el->checkState(1) == Qt::CheckState::Unchecked)
+            if (el->checkState(2) == Qt::CheckState::Unchecked)
             {
                 createdAron = nullptr;
                 return;
@@ -523,7 +523,7 @@ namespace armarx::skills::gui
         if (i->getMaybe() != armarx::aron::type::Maybe::NONE)
         {
             // its a maybetype. We have to check the state
-            if (el->checkState(1) == Qt::CheckState::Unchecked)
+            if (el->checkState(2) == Qt::CheckState::Unchecked)
             {
                 createdAron = nullptr;
                 return;
@@ -560,7 +560,7 @@ namespace armarx::skills::gui
         if (i->getMaybe() != armarx::aron::type::Maybe::NONE)
         {
             // its a maybetype. We have to check the state
-            if (el->checkState(1) == Qt::CheckState::Unchecked)
+            if (el->checkState(2) == Qt::CheckState::Unchecked)
             {
                 createdAron = nullptr;
                 return;
@@ -597,7 +597,7 @@ namespace armarx::skills::gui
         if (i->getMaybe() != armarx::aron::type::Maybe::NONE)
         {
             // its a maybetype. We have to check the state
-            if (el->checkState(1) == Qt::CheckState::Unchecked)
+            if (el->checkState(2) == Qt::CheckState::Unchecked)
             {
                 createdAron = nullptr;
                 return;
@@ -634,7 +634,7 @@ namespace armarx::skills::gui
         if (i->getMaybe() != armarx::aron::type::Maybe::NONE)
         {
             // its a maybetype. We have to check the state
-            if (el->checkState(1) == Qt::CheckState::Unchecked)
+            if (el->checkState(2) == Qt::CheckState::Unchecked)
             {
                 createdAron = nullptr;
                 return;
diff --git a/source/RobotAPI/libraries/skills_gui/aron_tree_widget/visitors/AronTreeWidgetCreator.cpp b/source/RobotAPI/libraries/skills_gui/aron_tree_widget/visitors/AronTreeWidgetCreator.cpp
index f36713e02b6d63258a028b35193d92f4aa7bb191..f9fd371e2e9c1b8c14f9e257e8e1dd6b26ccf198 100644
--- a/source/RobotAPI/libraries/skills_gui/aron_tree_widget/visitors/AronTreeWidgetCreator.cpp
+++ b/source/RobotAPI/libraries/skills_gui/aron_tree_widget/visitors/AronTreeWidgetCreator.cpp
@@ -104,7 +104,7 @@ namespace armarx::skills::gui
 
         if (i->getMaybe() != armarx::aron::type::Maybe::NONE)
         {
-            createdQWidgetItem->setCheckState(1, Qt::CheckState::Unchecked);
+            createdQWidgetItem->setCheckState(2, Qt::CheckState::Unchecked);
         }
         createdQWidgetItem->setText(1, QString::fromStdString(defaul));
         createdQWidgetItem->setText(2, QString::fromStdString(i->getShortName()));
@@ -137,7 +137,7 @@ namespace armarx::skills::gui
 
         if (i->getMaybe() != armarx::aron::type::Maybe::NONE)
         {
-            createdQWidgetItem->setCheckState(1, Qt::CheckState::Unchecked);
+            createdQWidgetItem->setCheckState(2, Qt::CheckState::Unchecked);
         }
 
         parentOfCreatedObj->addChild(createdQWidgetItem);
diff --git a/source/RobotAPI/libraries/skills_gui/aron_tree_widget/visitors/AronTreeWidgetSetter.cpp b/source/RobotAPI/libraries/skills_gui/aron_tree_widget/visitors/AronTreeWidgetSetter.cpp
index 4951555344ee891df2919466a43453cfbfb6d278..77887a000c8c5b7dddf955ba8eadeb1ec39b43ec 100644
--- a/source/RobotAPI/libraries/skills_gui/aron_tree_widget/visitors/AronTreeWidgetSetter.cpp
+++ b/source/RobotAPI/libraries/skills_gui/aron_tree_widget/visitors/AronTreeWidgetSetter.cpp
@@ -123,7 +123,7 @@ namespace armarx::skills::gui
 
             if (el->aronType && el->aronType->getMaybe() != armarx::aron::type::Maybe::NONE)
             {
-                el->setCheckState(1, Qt::CheckState::Checked);
+                el->setCheckState(2, Qt::CheckState::Checked);
             }
         }
     }
@@ -158,7 +158,7 @@ namespace armarx::skills::gui
 
             if (el->aronType && el->aronType->getMaybe() != armarx::aron::type::Maybe::NONE)
             {
-                el->setCheckState(1, Qt::CheckState::Checked);
+                el->setCheckState(2, Qt::CheckState::Checked);
             }
         }
     }
@@ -313,7 +313,7 @@ namespace armarx::skills::gui
 
         if (el->aronType && el->aronType->getMaybe() != armarx::aron::type::Maybe::NONE)
         {
-            el->setCheckState(1, Qt::CheckState::Checked);
+            el->setCheckState(2, Qt::CheckState::Checked);
         }
     }
 
@@ -338,7 +338,7 @@ namespace armarx::skills::gui
 
             if (el->aronType && el->aronType->getMaybe() != armarx::aron::type::Maybe::NONE)
             {
-                el->setCheckState(1, Qt::CheckState::Checked);
+                el->setCheckState(2, Qt::CheckState::Checked);
             }
         }
     }
@@ -353,7 +353,7 @@ namespace armarx::skills::gui
 
             if (el->aronType && el->aronType->getMaybe() != armarx::aron::type::Maybe::NONE)
             {
-                el->setCheckState(1, Qt::CheckState::Checked);
+                el->setCheckState(2, Qt::CheckState::Checked);
             }
         }
     }
@@ -368,7 +368,7 @@ namespace armarx::skills::gui
 
             if (el->aronType && el->aronType->getMaybe() != armarx::aron::type::Maybe::NONE)
             {
-                el->setCheckState(1, Qt::CheckState::Checked);
+                el->setCheckState(2, Qt::CheckState::Checked);
             }
         }
     }
@@ -383,7 +383,7 @@ namespace armarx::skills::gui
 
             if (el->aronType && el->aronType->getMaybe() != armarx::aron::type::Maybe::NONE)
             {
-                el->setCheckState(1, Qt::CheckState::Checked);
+                el->setCheckState(2, Qt::CheckState::Checked);
             }
         }
     }
@@ -398,7 +398,7 @@ namespace armarx::skills::gui
 
             if (el->aronType && el->aronType->getMaybe() != armarx::aron::type::Maybe::NONE)
             {
-                el->setCheckState(1, Qt::CheckState::Checked);
+                el->setCheckState(2, Qt::CheckState::Checked);
             }
         }
     }
@@ -413,7 +413,7 @@ namespace armarx::skills::gui
 
             if (el->aronType && el->aronType->getMaybe() != armarx::aron::type::Maybe::NONE)
             {
-                el->setCheckState(1, Qt::CheckState::Checked);
+                el->setCheckState(2, Qt::CheckState::Checked);
             }
         }
     }