No, once you make a move (at least on this site) you have to play the postion as it is. Now, you can ASK if he could move his queen, rook, etc. to move and then you can undo your mistake (as long as you didn't capture obviously) and then he can undo his last move which allows you to make the original move you intended.
Hope this helps.
I don't want the move back, exactly, I resigned. I want to be able to copy and paste the moves into a new game and he and I could play it from where we left it on out -- was I clear?
It would be kind of neat if you could get a famous game from "GAme Explorer," e.g., and copy the moves for say the first 20 moves -- then invite a buddy to play it out from that point as an unrated game to see if you and he could come up with the machinations that made the game famous. That would mean what, starting a new game and pasting in the moves up to a certain point?
I don't think I am explaining what it is that I want very well.
Can a buddy and I replay a game from the point where I made a blunder and replay it from that point on without the blunder?