Reminder Function on Start-up

I want to use KOrganizer/Pi to manage my private dates.
As I am not running Korganizer all the time or each
day, it is necessary to have a reminder function on
start-up (via autostart of Windows etc.) to get all
alarms in period beginning with sart-up until the date.
E.g. bithday of xxxx at 21.06., alarm set to 7 days,
start-up of PC on 16.06.: The reminder function shows
the date (if possible with the remaining time). The
reminder shall display the dates until they are
confirmed by the user, even if they are in the past
(then with negative remaining time).

It would be great with the background colour in the
remaining board could be set in dependence of the
remaining time e.g. green if they are in the future,
yellow if they are exact at the day of start-up, red if
they are in the past.

Contact:

thomba810@yahoo.de

Kind regards
thomba810