I left message for Sashazur. However this half and quarter screen seems a general problem.
Problem seems to be associated with windows speedup "fast rom emulation. Applies to 2000 and XP.
Right click Wordstar icon > properties > screen > performance > untick fast rom emulation. Set all other sets to full screen
This fix sometimes works OK - sometimes there is an opening problem and the full screen appears after the ctrl OP preview command is used and closed. This seems also to effect the screen resolution. Win 95 emulation seems to help also. Errol