Textmaker not printing both sides, despite printer settings

[Panch]

Using the direct print button, no preview, Textmaker prints on the fronts of pages only, no two sided back printing. This is despite the fact that my printer settings in Devices and Printers is for two-sided printing, both "Default" setting and the "Eco" setting. [HP Laserjet]
But if I use Print Preview, I do get two sided printing. This is presumably because with Print Preview, there are settings for printing that are part of Textmaker, it looks like to me.
Why isn't Textmaker picking up the actual printer defaults on my printer software?
I do get two sided printing with my other apps, and I think I did with Freeoffice, and previously with MSFT Word, but not now with Office NX.

[SuperTech]

Thank you for the post, but did you customize the printer setting from setup button after selecting your desired printer?