fix variable name and declaration

src/core/PlayArea.ttslua

@@ -10,6 +10,9 @@ DEBUG = false
 -- we use this to turn off collision handling until onLoad() is complete
 COLLISION_ENABLED = false
 
+-- used for recreating the link to a custom data helper after image change
+customDataHelper = nil
+
 local SHIFT_OFFSETS = {
   left  = { x = 0.00, y = 0, z = 7.67 },
   right = { x = 0.00, y = 0, z = -7.67 },
@@ -54,7 +57,7 @@ end
 -- data to the local token manager instance.
 ---@param args Table Single-value array holding the GUID of the Custom Data Helper making the call
 function updateLocations(args)
-  local customDataHelper = getObjectFromGUID(args[1])
+  customDataHelper = getObjectFromGUID(args[1])
   if customDataHelper ~= nil then
     tokenManager.addLocationData(customDataHelper.getTable("LOCATIONS_DATA"))
   end

src/core/PlayAreaSelector.ttslua

@@ -104,7 +104,7 @@ function updateSurface(newURL)
     playArea.setCustomObject(customInfo)
 
     -- get custom data helper and call it after reloading
-    local guid = playArea.getVar("custom_data_helper_guid")
+    local guid = playArea.getVar("customDataHelper")
     playArea = playArea.reload()
 
     if guid ~= nil then