Hello CCE,
Because Quik Check for Windows is a Windows-based product, its interaction with dot matrix printer drivers may not be fully supported. More specifically, it is often not possible for a Windows application to recognize the page breaks for a dot matrix printer driver.
The key to allowing you to print checks on your dot matrix printer is setting up a form feed for 7" on your printer. In other words, can you set up your printer, either through dip switches or menus on the printer, or through the driver itself, to have the page length as 7"? When you press the form feed button on the printer, it would eject only 7" and not 11". If you can do this, then you will have success printing your checks.