diff --git a/ExpCore/GuiParts/center.lua b/ExpCore/GuiParts/center.lua
index 59c7761b..ec6408ef 100644
--- a/ExpCore/GuiParts/center.lua
+++ b/ExpCore/GuiParts/center.lua
@@ -30,7 +30,7 @@ function center.clear(player)
 end
 
 function center._center.open(event)
-    local player = Game.get_player(player)
+    local player = Game.get_player(event)
     local _center = Gui._get_data('center')[event.element.name]
     local center_flow = center.get_flow(player)
     if center_flow[_center.name] then center.clear(player) return end
@@ -46,38 +46,45 @@ function center._center.open(event)
         if not success then error(err) end
     else error('No Callback on center frame '.._center.name)
     end
+    player.opened=center_frame
 end
 
 function center._center:callback(frame)
-    frame.focus()
-    local tabs = self.tabs
-    local tab_bar_scroll = frame.add{
-        type='scroll-pane', 
-        name='tab_bar_scroll', 
-        vertical_scroll_policy='never', 
-        horizontal_scroll_policy='always'
-    }
-    local tab_bar = tab_bar_scroll.add{
-        type='flow',
-        direction='horizontal',
+    local tab_bar = frame.add{
+        type='frame',
         name='tab_bar'
     }
+    local tab_bar_scroll = tab_bar.add{
+        type='scroll-pane', 
+        name='tab_bar_scroll', 
+        can_scroll_horizontally=true,
+        direction='horizontal'
+    }
+    local tab_bar_scroll_flow = tab_bar_scroll.add{
+        type='flow', 
+        name='tab_bar_scroll_flow', 
+        direction='horizontal'
+    }
     local tab = frame.add{
+        type ='frame',
+        name='tab',
+        direction='vertical'
+    }
+    local tab_scroll = tab.add{
         type ='scroll-pane',
-        name='tab', 
-        vertical_scroll_policy='auto',
-        horizontal_scroll_policy='never'
+        name='tab_scroll', 
+        can_scroll_horizontally=false
     }
     local first_tab = nil
-    for name,button in pairs(tabs) do
-        local first_tab = first_tab or name
-        button:draw(tab_bar)
+    for name,button in pairs(self.tabs) do
+        first_tab = first_tab or name
+        button:draw(tab_bar_scroll_flow)
     end
-    self.tabs[first_tab](tab)
-    tab.style.minimal_height = 300; tab.style.maximal_height = 300
-    tab.style.minimal_width = 500; tab.style.maximal_width = 500
-    tab_bar_scroll.style.minimal_height = 60; tab_bar_scroll.style.maximal_height = 60
-    tab_bar_scroll.style.minimal_width = 500; tab_bar_scroll.style.maximal_width = 500
+    self._tabs[self.name..'_'..first_tab](tab_scroll)
+    tab_scroll.style.height = 300
+    tab_scroll.style.width = 500
+    tab_bar_scroll.style.height = 80
+    tab_bar_scroll.style.width = 500
     frame.parent.add{type='frame',name='temp'}.destroy()--recenter the GUI
 end
 
@@ -88,10 +95,10 @@ function center._center:add_tab(name,caption,tooltip,callback)
         name=self.name..'_'..name,
         caption=caption,
         tooltip=tooltip
-    }.on_event('click',function(event)
-        local tab = event.element.parent.parent.parent.tab
+    }:on_event('click',function(event)
+        local tab = event.element.parent.parent.parent.parent.tab.tab_scroll
         tab.clear()
-        local frame_name = tab.parent.name
+        local frame_name = tab.parent.parent.name
         local _center = Gui._get_data('center')[frame_name]
         local _tab = _center._tabs[event.element.name]
         if is_type(_tab,'function') then
@@ -102,4 +109,8 @@ function center._center:add_tab(name,caption,tooltip,callback)
     return self
 end
 
+Event.register(defines.events.on_gui_closed,function(event)
+    if event.element and event.element.valid then event.element.destroy() end
+end)
+
 return center
\ No newline at end of file
diff --git a/ExpCore/GuiParts/inputs.lua b/ExpCore/GuiParts/inputs.lua
index f0b035d0..94a6ac5f 100644
--- a/ExpCore/GuiParts/inputs.lua
+++ b/ExpCore/GuiParts/inputs.lua
@@ -318,13 +318,12 @@ function inputs.add_slider(name,orientation,min,max,start_callback,callback)
     }
     slider.data._start = start_callback
     slider.data._callback = callback
-    slider.data.max = max
     slider:on_event('slider',function(event)
         local slider = Gui._get_data('inputs_'..event.element.type)[event.element.name]
         local player = Game.get_player(event)
         local value = event.element.slider_value
         local data = slider.data
-        local percent = value/data.max
+        local percent = value/event.element.get_slider_maximum()
         if is_type(data._callback,'function') then
             local success, err = pcall(data._callback,player,value,percent,event.element)
             if not success then error(err) end
diff --git a/control.lua b/control.lua
index 8742254d..7cfe05f0 100644
--- a/control.lua
+++ b/control.lua
@@ -49,7 +49,9 @@ center.add{
     caption='Gui Center',
     tooltip='Just a gui test'
 }:add_tab('tab-1','Tab 1','Just a tab',function(frame)
-    frame.add{type='lable',caption='Test'}
+    frame.add{type='label',caption='Test'}
 end):add_tab('tab-2','Tab 2','Just a tab',function(frame)
-    frame.add{type='lable',caption='Test 2'}
+    for i = 1,100 do
+        frame.add{type='label',caption='Test 2'}
+    end
 end)
\ No newline at end of file