I know Tianpeng Wang wrote a Delphi DLL wrapper for AutoItX but I have also written one that I think is just slightly more robust.
The advantages of the wrapper I have created are:
1. Dynamically loaded so no error with be thrown if DLL is not found on the path. You can query boolean AutoItXDLLLoaded property to find out if it is loaded. This will allow your application to function normally if the DLL is not found. The other wrapper is statically linked to the DLL and throws a cryptic e