Could you maybe add here where the markers are stored (i.e. variable name) so that it is straightforward for everybody to work on that ToDo?
On the other hand, I'm actually not sure if the merge operation should handle that. For example, in the case the operation removes the middle start- and end-markers, what about the data inbetween these markers - whould this data be windowed? If yes, this it not what should be done, since the experiment was not running during this time. I think this problem has to be solved in the windower in the way that the start-marker *always* (not only once like it is at the moment) works as a switch-on and the end-marker as a switch-off of the windowing procedure. What do you think?