Sales Order & Invoicing Issues

Hi,

I have below issues. Please clarify.

1) If a Credit Hold is applied to a customer, will the system put the customer orders on hold at Entered stage or Booking stage, i.e., does it allow entering but not allow booking?

2) If a Credit Hold is applied to a customer, will the system still kick off manufacturing orders to build the product or allow purchasing to issue PO’s for direct shipment?

3) Invoices are being split for service and sales items, they need to be grouped on one invoice. We tried using fufilment sets, but it will not allow a service item to be added to the set.Customers do not want to recieve multiple invoices. How to achieve this?