Currency field is read-only when orders are entered in the Customer Center for Multi-Currency Customers

Description:
When a Multi-Currency customer creates Sales Orders in the Customer Center, the Currency field is read only which prevents the ability to select another type of currency for that transaction.

Solution:
Customize the preferred Sales Orders form for the Customer Center role. Make sure that the Display Type for the Currency field is set to Normal.

Note: This is also applicable for orders entered in the user interface, not just in the customer center.