COMException loading the Intellisense XLL using VBA

Originally [reported](https://groups.google.com/d/topic/exceldna/PfNigj7oAGE/discussion) by @FastExcel in the mailing-list:

>
> I get this error message from DNA Intellisense
>
> ```
> "Runtime [Error] Unhandled exception in async delegate call. : COMException - Invalid index. (Exception from HRESULT: 0x8002000B (DISP_E_BADINDEX))"
> ```
>
> But I only get it when loading the Intellisense xll using VBA `Application.RegisterXLL` from the VBA Workbook Open event.
> (The workbook contains the intellisense xml)
>
> Once the workbook has opened `RegisterXLL` works OK. Looks like some kind of sequencing problem.
>
> https://groups.google.com/d/topic/exceldna/PfNigj7oAGE/discussion
>