Is there a way to change the Control-M Workload Automation Client screens and color settings?  For example, can the background color on the "Monitoring" screen be changed? 

The following video demonstrates this solution:

The background colors can be changed via the Map settings under File->Options->Map-> Background color.

To change the background color for the Monitoring domain, change the "Monitoring ViewPoint" color.

Additional information:

The changes are stored in the "ClientUserSettings.xml" file which is located under the "AppData" directory, for example, C:\Users\<username>\AppData\Roaming\BMC Software\Control M Enterprise Manager\8.0.0.0\Default\ClientUserSettings.xml