In New experiment, you open a specially defined file browser where you find and choose the set of different pos-files that form your experiment.
With Open old experiment, you open an ordinary file browser where you choose a single experiment file to be analyzed.
With Save experiment you may save the newly formed experiment file if not already stored
With Save experiment as you may store a data set under a new name and thus duplicate it
With Remove experiment id from person file you will open a new dialog where you may remove one or more of the files shown in the last used list below this menu
Click on a file in the list below Remove menu to open immediately the last used data set.