ICal won't recognize calendars in a calendar group

Question

First - I do not use the cloud, everything is stored on my local hardDisk
Second - the problem is only with iCal. Other programs can see calandars within calendar groups just fine.
Third and most importantly - I apologize in advance for misspelling calendar (or anything else) as I am sure to do so many times.
My problem: All of a sudden iCal stopped recognizing anything inside a calendar group.
I am running Mountain Lion 10.8.3.
I have multiple calendar groups, all containing calendars inside them and a slew of events for each.
When I click on a calandar within a group and add a new event it popps up with the right color, indicating that it will be saved within that calandar group, yet inside the actual event (in the edit screen) the calandar associated with it is null. Specifically I can't choose anything because everthing is grayed out. The only thing showing are the names of the various calendar groups I have, but none of the calandars inside those groups show up for me to select them.
Notice that the new even is GREEN indicating that it will go into the World Holiday's calendar inside the group Holidays. Yet inside the details of the even it shows that the associated calandar is Lightfoot, the only calendar not inside a group. The only way to make World Holidays an option is to move it out of the group, but that defeats the purpose of groups.
As stated before, the calendar groups show up and work fine in other programs, the problem is unique to iCal alone. Here is a screenShot of mail as I try to add a new even from there.
See how it is giving me the option to put the event in ANY of the calandars whether they are inside a group or not. This is how iCal was working up until Tuesday the 19th. This is also what I just finished doing when it broke. I have tried the following with no success:
- deleting all the calendars/calendar groups and working from a clean/error free archive of iCal
- deleteing my cache files
- installing a dummy user with admin privelges to see if the problem ports over
- reinstalling OS X (not erasing my data but in essence reinstalling iCal)
- verifying the disk to find any errors (there were none)
- reparing disk permissions (they were all fine but I repaired them anyway)
- contacting apple support (nice guy, but so far can't figure it out either)
It appears to be a hierarcy issue inside of iCal alone. It is as if anything inside a calendar group (calandars and events) is unreadable by iCal, like the hierarchical structure is corrupt or there is a bad line of code in there somewhere. Any ideas on what I should try and do to fix it?
Thanks!

Answer 1

I too am having this difficulty.  It just showed up today (3/27) and nearest as I can figure, is somehow tied to the latest Mountain Lion update since I just installed that from the App Store.  That said, I'm no closer to figuring out what to do about it.
I am also running 10.8.3 and am steering clear of the Cloud because it doesn't support calendar groups.
Like you, I can get things in the right calendar/color if I click that calendar then add the event.  But if I then go into the individual event it is being labeled as something else.  I think it is actually putting it in the correct calendar, because if I click between events and watch the calendar bar on the left, it switches between the different calendars and groups appropriately.  It is a bit frustrating though that if I want to switch an event's calendar assignment, I now have to re-enter it, rather than just switching it through the edit pane or by right-clicking.
Here's hoping someone out there will see this and have a solution.
Cheers!