It works fine on XP..and in advanced options you can choose other sounds...even .wav files...to warn you. It can also be linked to the 'insert' key...and with a different warning sound. I often have problems with wiping out what I have typed. (also can be linked with 'num-lock' key, but that is not usually a serious problem for me)

There is a hot-key combo to turn the program OFF..(like I'm sure I'll have to do for my wife, who types well & fast and doesn't like little 'beeps' when she's working.. ;>)