The lists on the right hand side of the main window show alarms which occurred in the specified period. The upper list shows past alarms, the bottom one coming alarms. Right-clicking one of the lists will bring up a pop-up menu, with some of the commands which also appear in the alarms menu. The commands will do the same as the corresponding ones in the alarms menu.
Note that alarms are only shown in these lists if they're turned on and the alarm group they're in is turned on.
Also note that these lists will require quite some calculations, especially if there are a lot of alarms. Turn the lists off to speed up the program.
Then you may also note that if there is an extremely large number of alarms to sound in the specified period, the lists will be turned off automatically, because it might take a lot of time to show the entire list. If this happens, you should either select a shorter period or turn off the often sounding alarms.
Note: if you have set a periodical alarm with a short period length and a condition which will only be true after a lot of these periods from the current date and time, this will take a lot of calculation time. If the calculations take too much time, the alarm will not be show in the list of upcoming or past alarms. So for example an alarm with a period length of 1 hour and an 'advanced' expression as 'YEAR == 2125' will not be shown in the list of upcoming alarms, because it takes too much calculation time. (This is done because the program can't be sure there exists such a date and time. This prevents the program to enter a never ending loop when you choose an advanced condition like 'DAYOFMONTH == 34'.)