RunWorkerCompleted, the operation is not implemented error

I am trying to use Chem4Word add-in for word on my Windows Vista ultimate machine.
I am totally new to this and trying to learn it step by step. When I try to insert anything in my regular Word document, I get the following error message.
worker_RunWorkerCompletes: The method or operation is not implemented.
If I click Ok, on the error message it does not take me anywhere. Again when I try to perform the same action, I receive the error message.
Any help on this is appreciated.
