When you customize the report, go to the "Color-Coding" section at the bottom of the report settings.
Select the option for "Write a formula".
Now you can write a formula using a combination of fields. You'd want the final output to be a hex color e.g. "#cc000", or some of the color words will work too "Green", etc.
Here's the online help on color coding for reports - look at the Formula examples section, particularly "Color-code records based on a combination of fields".
At the bottom of the calendar report page there are options for color coding. Here is an example of color coding used for a company vehicle scheduling app:
It is very easy to use with the latest enhancements Quick Base has made. To color code based on more than one field, just create a formula field that evaluates your multiple fields and then color code using your formula field based on the result of the formula evaluation.
If you still need more help, post specific details about what you are trying to accomplish; i.e. I have action items on a calendar that i want to color code based on status and deadline etc...
