The code is working. However, all it does is set the value of variable strForm. The code does nothing with the variable. What do you want - to open a form or report?
DoCmd.OpenForm strForm, , , "OrderID=" & Me.OrderID
BUT, the form opens with #Name? in textboxes. frmCustomers_sfrmOrders is open to a record Transfer type with OrderID 1. There is no OrderID 1 in qryApparelOrderDetails. I moved to OrderID 5 and form opens correctly.
Need to fix data. Time to purge and start from empty?
If you set breakpoint in the procedure you will see the execution. Refer to link at bottom of my post for debugging guidelines.