This is more of a perception problem than a technical one. If you are more interested in hiding the issue than actually fixing it, launch the report generator in the background (system() with an & at the end) and have it write its output to a file. Then fire up a message box that says "report generation in progress" and has no clickable buttons. Next schedule a subroutine to run every 0.5 seconds to see if the report generation is done, and once it is, destroy the message box and slurp in the generated report.

Although as ugly as sin, this doesn't require any fancy threading, and doesn't block the application from redrawing the windows. And that annoying message box (and you know it will annoy your users) will keep them busy/pacified for the 5 seconds or so you said that are needed to generate the report. You can put a countdown or progress bar on that message if you want to get fancy and can really estimate when it will be done.

- doug