CT FMLI Taxable Gross

Does anyone else pay expenses through Payroll, such as travel reimbursement, that should not be considered taxable for CT FMLI? If so, how do you set up the earnings code so it is excluded? We are seeing "All Gross" as the Base Gross on the Taxable Gross Definition Table, and nothing we do for configuration will remove these expense-type earnings codes from the calculation.

Thank you!