I think the difference is because in TIFFs, PCs & Macs use 0 & 1 opposite for B&W, and the Alpha Channel Mask.
When I pasted a Preview Copy of mixed text & Picture into Graphic Converter, the Picture was good, but the text was black on black... Flattened the Alpha Channel Mask and the text showed perfectly, black on white.
Selecting All & copying in Graphic Converter then pasted correctly into NeoOffice, which the previous pasting from Preview was black text on black.
Word most likely would work the same.
GraphicConverter...
http://www.macupdate.com/info.php/id/263