I can confirm this issue, have it here as well, to be more complete as TS, I created a dumpfile
I've created the dump using the 32-bit version of rainlendar. I tried the 32-bit version after the 64-bit one to test if the 32-bit version crashes the same way.
The crash only happens if rainlendar wants to give an alert right after syncing with the Google Calendar I use. I do not know if alerts from other sources than Google Calendar crash the program as well.
Hope this information is helpful.
(file password is "rainlendar2")