Dino,
What do you mean by this? I have to assume that what you are talking about is that you have a cursor on the graph, move it, and want to move it back using Ctrl-Z. Is this correct?
Ctrl-Z is a development environment option to undo development mistakes. It also happens to work with everything else since practically anything can be a "mistake." A lot of options are not available in the Run-time Engine that are available in the development environment.
Randy Hoskin
Applications Engineer
National Instruments
http://www.ni.com/ask