From the OP's return to let us know when everything was ok:
Thanks for the response. I thought maybe being a guest, I wouldn't get much of a reply. I did what Sasha said and re-installed my Dnd anthology to C:/Games and currently the EasyTutu is working and is already past the bgate2.mpi mess up.
Thanks for the help too, William. Lets see if this continues to work.
It's still on the fence. I'd like to read it as the OP followed the instructions I posted and everything worked fine without needing the bgate2.mpi file. However, the OP didn't explicitly state that they didn't need it either.
I too would like to know for sure so that the instructions given when people have problems are accurate and not giving false information. Obviously downloading the file and putting it into the game directory isn't really going to hurt, but still would rather be accurate than not.
If I remove the bgate2.mpi file from my BG2 install, would that make it think it is the anthology version? If so, I'm willing to test the EasyTutu installer that way....