In Calendar 6 (mountain lion) when I use command E to bring up an edit window after I make changes I haven't been able to find a keyboard short cut to close that window and keep whatever info I've entered or changed.
I've searched quite a bit on this question. I've seen using Esc suggested, but that cancels the info/changes. I think that may have worked for older versions of (iCal).
Best Answer
As far as I'm aware, there is no single keyboard shortcut to do this. What you can do is this; after completing your edit, hit "Command E" followed by the space bar. Command E will collapse the edit window and the space bar will dismiss the info box while preserving your edits.