Looping over calendar_events, tag names and help with condition check

I am using the calendar events addon from solspace. I am trying to display a summary of 2 upcoming events. I have this code:

{exp:calendar:events limit="2" sort="asc" dynamic="off" status="current"}
    <li><a href="http://{url}">{title}</a></li>
{/exp:calendar:events}

My questions are

1. The channel called calendar_events has 7 fields but none relate to the title or the url. However, in the above {title} produces the name of the entry but the {url} comes back blank. What is the tag identifier for the url of an entry?

2. Is there a way I can sort the retrieved events by the date on which they occur? For example if I have 3 events in March, created in this order: March 1st, March 15th, March 10th I want the March 1st and March 10th events, not the 15th. The channel has a field called {event_dates_and_options} which is where I specify the date and time of the event.

Thanks, Andrew