(stack: ubuntu 12.10, apache 2.2, mysql 5.5, and PHP5.4.6)
steps to reproduce:

on a fresh install with sample data (calendar module download was previously patched with 1471400-12.patch because of problem described here: #1591388 , and nodemaker/modules/contrib/calendar was updated before running install), navigate to Events. click "year" button, then click on "next" year button to bring up 2013. Scroll down to Feb and click Feb 6. On display of date page, the following error messages are provided:

Notice: Undefined index: groupby_times in template_preprocess_calendar_day() (line 269 of web_root_path/profiles/nodemaker/modules/contrib/calendar/theme/theme.inc).
Notice: Undefined index: groupby_times in template_preprocess_calendar_day() (line 273 of web_root_path/profiles/nodemaker/modules/contrib/calendar/theme/theme.inc).

Looks to be another PHP 5.4 problem with the calendar module. But wait - there's more:
click on "DrupalCon Sydney" title, and on display of event detail page the following additional errors are displayed:

Strict warning: Only variables should be passed by reference in addressfield_staticmap_clean_address() (line 391 of web_root_path/profiles/nodemaker/modules/contrib/addressfield_staticmap/addressfield_staticmap.module).
Strict warning: Only variables should be passed by reference in addressfield_staticmap_clea_address() (line 391 of web_root_path/profiles/nodemaker/modules/contrib/addressfield_staticmap/addressfield_staticmap.module).
Notice: Undefined offset: 2 in nm_events_preprocess_page() (line 65 of web_root_path/profiles/nodemaker/modules/apps/nm_events/nm_events.module).