In Live chess, once you move a piece it's moved. There isn't any way to cancel a move there like in Online (the correspondence, multi-day games here). You can however, put the piece back on its original square before you let go of the mouse button (can be very handy for faster time controls).
In over the board play, rules are even more strict. There, as soon as you touch a piece you have to move it!
i think i have lost critical placement at least 5 times and the last 1 was just now.it seems i have no control moving pieces at crutial times. i think i have lost 4 games because of this. the losses all happened when i started to move a piece to see an outcome and the piece via your program stayed in place and i had no way to recover. i aborted all 4 times. in my opinion; this isn't fair. if you want me to play this way, pls change your programming.