I can't print my system from the Corvid Editor.

Usually that is caused when the Printer Drivers do not match the Printer model. Printing the tree structure seems to require functions in the printer that most other programs do not call for. For example an HP DeskJet 900 driver may work most of the time for an HP DeskJet 932C but will not work correctly when printing the trees. So go to Start | Settings | Control Panel | Printers and make sure you have the correct driver for your specific printer. Also make sure the correct driver is the default that Exsys Corvid is using. When it is printing, right mouse click on the printer icon (on the task bar near the clock), and go to File | Properties and see if it matches.