Related Questions:
How do I change the colors for Bookings?
Can I customize my Bookings colors?
How do I control the color of my Bookings on the calendar?
Answer:
The only colors that are customizable in Event Temple are the colors associated with Spaces.
When a Space is associated with an Event, the Event will inherit that color on the Calendars and the Booking will inherit the color of the earliest Event (if there is only one Event, it will inherit the color of that one).
The colors for Lead, Tentative, Definite and Lost Bookings are not customizable.