Dear all, I have been experiencing a bug in Athena, this is occurring in the most recent version 0.9.25, as well as the older versions I have used. The big is occurring when using the difference spectra window to produce difference spectra for a set of data. When I use the 'Plot difference spectra for all marked groups' function it will produce the plot but if I change any parameters in the main window and want to check how this has changed the difference spectra it will only plot the original difference spectra. To see the new difference spectra after the changes have been made I need to close Athena down completely and open it up again. If I just close the project and load in new data and try to plot the difference spectra for this new set of data it will still only plot the difference spectra for the old data. I have attached an Athena project file, please let me know if there is something different I need to do to change the difference spectra plot. Kind regards, Sinead Rowe