I am having the same issue many others are reporting. Under Calendar options I have it set to default to 30 minutes when creating a new meeting. However, when I create a new meeting request the default is zero. I can manually change it to what ever value I want. There is a BUG in the software! I cannot believe this software is being released to the general public in a few weeks. Outlook 2013, Windows 7 Pro.
The reminders go off as they are supposed. Microsoft please fix this ASAP.