You will need to rent a car to drive the 1.5 hours from the Denver airport. Since we're inviting our friends and family, I recommend booking flights as a group so you can share a rental car for the weekend.
Yes, there is a small parking lot and street parking.
The average temperature in May is a high of 65ºF and a low of 35ºF. Afternoon showers are common.
It could be! Bring something to keep you warm in the evening if you plan on being outside. There is a fire pit and heaters at the venue.