1. I'm not able to reproduce that on the demo site with IE 9, I click the link in timeline view popup and it goes to the event details.
2. It doesn't let you register after the event has begun, so the start time of the event is a factor.
Event recurrences creates separate events for each recurrence and they are tied together by a recurrence guid. Creating recurrences is a complex process, correctly figuring out the dates and times of each recurrence based on the original first event and accounting for crossing of time zone changes from daylight savings vs standard time at different times of the year etc, especially since it can go way out into the future it has to create each event and the friendly urls for each event, so it is done on a background task so it is not instantaneous creating nor deleting them but it is fairly quick.
Yes it is a limitation that you cannot update the recurrence without deleting it and recreating it for the reasons and complexities mentioned, it is easier to implement it by just deleting it and recreating it if you need to change it.
Hope that helps,