Thats an unusual problem! I've been creating the text boxes by simply selecting the New Text button on the tool bar and proceeding. I like to use Arial Narrow for my charts, and although I set this as the default it doesn't stay a default so I often copy and paste and existing text box to minimise the work in the changing fonts etc. I noticed when I looked at the top black text box, its format was set to Custom - not a conscious choice all this text was copied and pasted (then rearranged) from the text on the previous pages. So I changed only that one text box to black, then went to Print (rather than Export) and it worked perfectly!
My defaults are currently set at Arial Narrow 8 Black but a new text box goes to Arial Regular 8 Black. There is no Options | Fonts Mode | Embed True Type Fonts on my version. (TreeDraw Legacy Edition 4.2.2)
Thanks very much for your quick reply and a solution.