I have added the option of selecting axes for nexpy to plot. It is still preliminary -- no checks yet to make sure that x-axis and y-axis are uniquely selected and it hasn't been tested much yet. The zoom and/or change summation options is almost working, but I am adding a new library to the requirements list, wxmpl (at http://agni.phys.iit.edu/~kmcivor/wxmpl/<http://agni.phys.iit.edu/%7Ekmcivor/wxmpl/%29>). It is very straightforward to install (python setup.py install), at least on linux. Let me know if there are any problems on the mac. Jason