DecoTech™ v6.xx now remembers the last configuration you set for each kind of printout.  So you must configure the floor plan printout separately from the 3D perspective printout.

To do so, click the Print Setup button located at the right of the Print button in the Print the floor plan or in the Print the 3D perspective window.

Some printer drivers do not support correctly applications that do not use Image Color Matching and the result is a black printout.  To avoid that you need to disable the ICM of the printer driver.  In the Print Setup window, click the Properties button.  The window that will appear will be different for each printer driver so we cannot show you a screen capture of it.  You need to find something named ICM or Image Color Management or Image Color Matching.  This feature is often located in an advanced sub-window accessible via a button.  If the ICM is a check box simply unselect it.  If it is a multiple choices control, set it to none or disabled.