Well, here's a work-around:
- Create a png image of a rectangle in your favorite graphics editor, close in size/aspect ratio to the header/footer in your Prime worksheet. The background has to be transparent so you'll need to save it as a png file (a jpeg won't work, you'll get a white background that may or may not cover up your header/footer fields). You'll need a graphics program to do this - I used SnagIt, but GIMP or Paintbrush or anything that will save a png file should work as well. Once you've created this image and saved the png to a convenient location, you can use it over and over again for other worksheets.
- In the header, insert an image (Document tab), selecting the png file you created in step 1.
- Mouse select and size the rectangle to fill the header area. You'll want a little bit of "clickable" space to either side of the rectangle.
- Click outside the rectangle and type your header text, then move that text inside the box and position where you want it.
- Copy the rectangle image and past it in the footer to get a rectangle of exactly the same size as the one in the header.
- Create your footer fields and put them inside the rectangle.
Not as easy as clicking a button in Mathcad 15, but it's workable if you want the frames bad enough. If you create the frames in a blank worksheet and create a custom template, you can just open the "framed" template and start working.
