Can no longer see screens lower than 40 or 50%

 Something has gone wrong (Quark 8.5.1).

In order not to mis-align screens, I need to make them 70% or higher -- then after they are positioned, remember to lower them back to the percentage that I wanted.

 Or -- make a PDF of the file, because the screens show up nicely in the PDF.  But this causes a lot of back and forth.

 Any ideas?