Could Not Find LangDialog.exe

I have just found out about ExperienceUI, so downloaded and installed it and am quite impressed with it!

Small problem; I want to set my installer up for multiple languages, but when I add this line in .onInit

   !insertmacro XPUI_LANGPAGE_DISPLAY

  I get this error:

   Could Not Find C:\Program Files\NSIS\ExperienceUI\Contrib\ExperienceUI\LangDialog.exe

Can anyone tell me why it's happening and how to fix it?

Thanks in advance,

Steven.