If I select a passage of text and then change font, the whole file changes to the new font. Secondly, if I then print, the font change is ignored in any case, and whole file prints in the default font.
This isn't a text editor with functions similar to Microsoft Word to change the font for a certain paragraph. If you change the font for a portion of text, then it will change for the whole documents. This is something similar to Notepad. However, it also prints in the same default font even if it's changed, as you said. I have tested and I can confirm this is happening. Unfortunately, there is no fix for this problem. Use OpenOffice instead. It will print with the fonts you choose and keep the font style you select for each of the paragraphs modified in the application.
Thank you for comprehensive answer. NoteTab ought to change their blurb to acknowledge these restrictions. Back to OpenOffice, then!