Customer Approves First
If this field is selected, then the Project Approver will not be notified of a pending project approval until the Customer has first approved the timesheet or expense report.
If this field is not checked, then the Project Approver and Customer approvals can occur in any order.
This setting will apply to the primary and alternate customers for this project.
This field is used in conjunction with the Time and Expense check boxes.
Customer Approves First - Behavior Clarification
If more than one project on a timesheet has a customer approver, and any one of those has the customer approves first check box checked, the status report will report all eventual approvers but the Manager and Project Approval queues will not see the items (that is, only the Customer approval queues will). This is true for all customer approvers for that timesheet/expense report (regardless of whether or not they're configured with Customer Approves First). Now then, as soon as any one of the Customer Approvers approves their project (even if other customer approvers on other projects on that timesheet/expense report are configured for customer approves first), those timesheets/expense reports will then be added to the Manager and Project Approvers approval queues. Perhaps not what you might expect, but how it currently behaves.