DTW 8.8 AR Invoice will not print on Add

We are developing a process ti import AR Invoices into SBO via the DI Server.

We want the Invoices to print as they are added.

The Print Preferences are set to Print on Add.

I am testing the process using DTW which I realise does not use the DI Server.

Even if the Printed field in the DTW OINV file is set to NO (psNo) the AR Invoice is imported with status of "Open - Printed" but does not actually print.

Any suggestions would be welcome.

Rgds

Tony