FileMaker has two methods to print in columns Down First or Across First.
When using DOWN first any summary parts are only the width of the column. When it reaches the end of the page it resumes at the top of the page next column.
When using ACROSS first summary parts are the width of the page. However any alternating row colors do not alternate as you'd first expect. Since all odd rows are on the left and the even rows are on the right (if using 2 columns).
My first attempt to create a FAUX DOWN with the full width summary parts. I soon realized that the script ends up modifying each record in the found set - this change data every time you wish to print the report.
The second version does the same thing but uses the Virtual List technique to produce the printed report not requiring changes to the source table.
This example only produces 2 columns but could be adapted for more then two columns.
If you have optimization suggestions please feel free to post a comment.