If KAlarm has begun crashing on loading, try entering kalarm & in the terminal and hopefully it will open fine. If it does, exit the program properly (ie: don’t just close the terminal), which you can do by right-clicking its icon in the system tray. Then restart KAlarm via its launcher and, with luck, it should now load without issue.
Did this information make your day? Did it rescue you from hours of headache? Then please consider making a donation via PayPal, to buy me a donut, beer, or some fish’n’chips for my time and effort! Many thanks!