AFAIK, PlanMaker applies the Normal style to empty cells. What font is set in your Normal style? On my machine (and I believe it is the default), the font for the Normal style is Arial, 10pt. If it is the same for you, edit the Normal style to have whatever you want to be the default font for the workbook.
The Normal style comes from the default document template (normal.pmv), rather than a preference setting. There are clear instructions in Help (search on 'template') for creating a new template and setting it as the default, so you can use your own settings for all documents.
Exactly! I have carefully setup my normal.pmv file to suit my preferences with font, row height, column width, vertical alignment, page margins and so on. In my case, my font in the normal template is lucida console 8.
After cutting and pasting I get Arial 10, which I realize is the default font in the original normal.pmv.
I just don't get it. I will double check and se if I have the same problem on the desktop. This "version" is a portable copy on a notebook.