I had a reminder window pop up this morning from the calendar. I usually just dismiss them but decided it needed to be removed now. I chose the menu option on the reminder windows to "Open". When I did, another window popped up but stuck underneath the Reminder window called, "Open Recurring Item". Both Windows became stuck open with no way to close them. As a result, none of the other features in doogiePIM worked either because the application was waiting for something to happen with those two stuck windows. Nothing else worked except shutting down doogiePIM. Upon choosing Shutdown, I received another error, "Oh my! Something unexpected happened." After restarting doogiePIM, I was able to open the calendar directly and remove the recurring event without issues.
(Version: 2.2.0.0 running in 64bit Windows 10, build 19041.572)

Hi Randall. Many thanks for reporting this.

The problem is due to "Modal" windows. These are the popup windows that request information and must halt main input to the rest of the application. eg: The "Recurring Details" window.

In a future version, I'll code it up so the modal window will appear on the top and not behind any larger modal windows.

I hope everything is going great and please, stay safe.